I think my Wolf allows me to rely on winning neutral more. I play Lucario with the assumption that I will only win neutral four times, so I try to go for a 0 to death combo whenever possible, hence why I lab a **** ton.
Yah, Wolf and the other spacies definitely have a more apparent neutral game than Lucario. Winning neutral four times is definitely the idea although extremely unlikely in practice. As you have experienced, it takes a lot of practice and labbing to be able to reliably combo against every character and practicing neutral is just as difficult.
Furthermore, Wolf covers a lot of Lucario's bad matchups (plumbers/floaties), but I still have bad matchups into Samus, Fox, and Falco (who should I play in these situations, btw). Furthermore, I can, vs most of the cast, wall people out with lasers as Wolf and then pick my approach based on laser play (hence why I suck at playing vs faster characters where lasering is a lot more dangerous, e.g. Wolf dittos). For my Wolf, I'm trying to become less laser reliant, trying to get flash setups, and incorporating waveshines/multishines more into my gameplay.
As the meta stands at the moment, Wolf has of the best match-up spreads in the game. According to the Community Match-Up Chart, Wolf only loses to four match-ups (Lucario, Marth, Samus, and Yoshi) whereas Lucario has twelve if I am counting it right. Take that with a grain of salt though. Lucario also struggles with the three match-ups you listed, but if you feel that your Wolf is on par with Lucario I would probably have to say Wolf. Marth is good secondary character in general but especially for Lucario, and according to the match-up chart , Marth goes even with Fox and Samus, again, all of which is debatable.
With Lucario, I can't pick my fights. You don't win neutral on Lucario, your opponent throws it away.
Yah, unfortunately, that's kind of the sad truth, but making an opponent lose neutral is winning neutral nonetheless. I might be overgeneralizing, but Project M for the most part features a cast that is to some extent or another primarily reliant on bait and punish gameplay. Basically the spacies, Diddy Kong, Mario, ROB, and Samus are a few characters that have a good neutral and basically from there the cast becomes more reliant on bait and punish, so it's not like a subpar neutral is exclusive to Lucario.
Lucario's neutral game is definitely not great. He has tools to avoid getting hit and to baiting opponent's into attacking, but his neutral will always be limited by his lack of approach options. While dash attack is rewarding when it hits it's slow, predictable, and laggy all of which make it very punishable. Fair is also a decent approach option but it can only be comboed into a special so it's kind of limited comparatively although it still has the potential to be effective. Something that I know I have mentioned in your reddit gameplay critique is using aura spheres to pressure your opponent. They are not as effective as Wolf's lasers but they have their uses. With the use of b-turnarouns, b-reverses, and wavebounces, aura spheres can be a decent neutral tool especially if you use b-tech aura sphere cancels for movement which makes actually throwing out an aura sphere more surprising. Although aura spheres are not particularly great projectiles, I think improving your usage of them will lend to something slightly closer to the experience of Wolf's neutrals (still lacking in comparison especially in the approach options though),
Lucario unquestionably requires a lot of patience. Lucario should basically never approach in neutral except maybe in an effort to bait an attack. If a Lucario player can not resist aggression, there will definitely be consequences.
On Wolf, I can force approaches and sometimes overwhelm people based on pure techskill. Basically, on Wolf, I can force my agenda down my opponent's throat, I can't with Lucario. I don't have to think about my opponent as Wolf (unless it's vs a Falco).
I don't know what it is like to play such a character, but that must be quite a feeling after having to deal with Lucario's limited approach options. Your situation kind of reminds me of iPunchKidsz playing Fox and his questioning why he still would play Lucario when he cold play Fox. It seems he found some reason to continue using Lucario since I don't believe he has played Lucario recently.
I also get a lot more frustrated when I'm playing Lucario. If I lose as Wolf, I'm like w/e. On Lucario, **** man, I've torn a hole in wallpaper from throwing a controller, tbh I'm surprised my controller hasn't shattered from all the times I've spiked it/thrown it. I don't play this game to have any fun, I play strictly for winning, which is my sole focus. I want 0 to deaths on some of the high PR players, I want to be able to play a set, then make a highlight reel from that one set. I want my opponent's resolve shattered after Game 1.
I don't exactly know how to properly respond to this. I think Lucario is not very forgiving and I know other players and personally experienced frustrating experiences with Lucario. It can be like rehearsing for a speech for hundreds of hours then when it's time to recite it you forget a word in the middle of it and sometimes you recover and finish it but most of the time the rest of it is ruined from there. I think because Lucario is so flowcharty it amplifies the frustration because you know beforehand exactly how a combo should progress, you've practiced and executed it many times, but when it matters you there is some input error or something and you get punished for it and have to put in the work to bait the opponent again. Also, since Wolf has been your secondary up to this point maybe you have at least slightly lesser expectations so your slightly more forgiving of Wolf.
I don't know what to say about your winning being your sole focus. The determination is good, but if it's not fun then I don't know what the point is unless winning is fun. I don't know. I know I play Project M because I find Lucario really fun to play and to theorize about even though it can be a frustrating experience at times. I would really like to be able to win sometime, but I can't realistically make that a ultimatum unless I know I have practiced and studied more so than most everyone else in my area, but that's not at all a priority for me.
So, if winning is your sole priority, then I would say in honesty that I think in the current meta Lucario might be the most overrated character in Project M. Although Lucario's combo game is great (also decent recovery) I think the ability to 0-death a character is negligible in some 20XX scenario in comparison to a reliable neutral. Despite having a less than spectacular matchup spread, a subpar neutral, and only national success from one player, Lucario is consistently placed as a high to top tier character. I don't blame the placement but sort of thinking does not seem to be consistent to other characters, but then again I don't really understand those kind of things so I trust the opinion's of others in that matter. The viability of Lucario has never been a concern for me regardless because I really enjoy using the character. Anyways, theoretically Wolf is probably the "better" character and you seem to have a more aggressive mindset that does not suit Lucario play well, so if winning is the sole priority then it makes sense for Wolf to be a better choice in character for you.
That being said, you haven't really made a case here why Lucario is an option for you and what about your Lucario is better than your Wolf. It's hard to look over what you said and not think that Lucario does nothing for you and the way you play Wolf is exactly what you are looking for.