bc1910
Smash Lord
I'd go one step further and say Gunner is pretty darn good.Not sure how to close this, really, but I do want to reaffirm that I don't think Gunner is bad. In fact, Gunner is pretty solid even. We have tons of ludicrous options, strong confirms, great projectiles, versatility, etc. Don't sleep on a Gunner if you run into one, because MU inexperience is legitimately a huge boon for us.
Specifically the 3332 set (grenade, Samus missile, angle-able rocket launch, bomb drop) has great potential and is pretty unique in how it operates. Most Gunner players seem to use the Samus Charge Shot custom, but I feel like you should just use Samus if you want to use that custom since her Charge Shot is better and her kit complements it better. Flame Pillar is also popular, but again, this just seems like a worse Arcfire/PK Fire (it has a TON of lag). With the 3332 set, Gunner has a unique projectile in the grenade launcher and exerts a huge amount of stage control with it, complemented by the bombs and missiles.
Gunner has clear weaknesses as a projectile specialist. He's slow, has a very poor disadvantage state, below average CQC and a fairly poor recovery. This leaves him particularly weak to characters who can get through his wall of projectiles and keep him in disadvantage for most of the match. Unfortunately this includes a lot of speedy top tiers like Pichu, Pikachu, Greninja and Inkling. Gunner particularly hates fast characters with good reflectors since they force him to use his projectiles more sparingly, meaning the Fox and Wolf MUs are not pretty. The custom 1 reflector can come in handy in these matchups, but bombs are still quite nice to ensure you don't get absolutely mauled up close.
If you can't abuse Gunner's weaknesses though, you're in for a hell of a ride. You're almost certainly not gonna outzone him and weaving through his projectiles to get 1 or 2 hits won't be enough to win the war of attrition unless you hit as hard as, like, Ganon, and most characters who hit that hard are almost never getting through the wall. The above set is hugely oppressive and works particularly well against opposing zoners and characters with poor mobility.
As far as normals go, Gunner's Uair is ridiculous (probably better than Palu's in a vacuum, be thankful it's on a character with ****ty mobility) and his other aerials do their jobs pretty well, especially Nair as a surprisingly effective get-off-me tool. All his tilts are good, particularly the Snake-esque Utilt, and dash attack is actually pretty nuts as a midrange option; it kills at reasonable percents and combos easily from his projectiles at lower percents. Gunner's ledgetrapping (for which he also uses his specials) is pure nonsense as well, grenades can cover every option while bombs prevent a neutral getup and Fsmash can hard punish any option without the need for strict timing.
Gunner probably loses to too many top tiers to be a meta pick but I can see him having serious value as a counterpick. I'm actually looking into him as a potential Snake counterpick now (if anyone has any thoughts on how the MU goes please let me know). I've been very impressed with him overall.