I have no idea what aspects of villager are the problem, but if we're really talking about a Dabuz-level villager, then I don't need to waste time telling you how punishable moves like Dash attack are, he won't be using them.
When villager plays defensively behind a seed and firing sling shots, keep passive. Shield won't run out after a few 3% hits, and it's not a race to see how fast you can get to him. Try crawling instead of walking. The low profile puts you under short hop slingshots that would have hit you, and the crawl has comparable speed to walking. If he summons lloyd rocket, use Fire Breath. The stream passes through to hit villager and destroys the rocket as soon as it becomes active. Fire Breath reaches about as far as his Fair and Bair, and I know I've forced Villagers out from behind a seedling by staying back with spurts of Fire Breath. Never hold it down, or you'll risk being open for his aggresive options. If he's doing that thing where he regrabs the ledge and fires Fair from there, that's when you want to respond aggressively. By giving up ledge invulnerability for regrabs, he's open to a Dair meteor, Dtilt, or even Bowser Bomb. If the tree is up, Fire Breath still passes through it, but consider tilting through it to extend hitboxes for your moves. It's great for covering his landings between slingshots.
Optimal stage pick is probably Battlefield, and Castle Seige for counterpick stage. Phase 1 of Castle Siege is bad if we're on the elevated side, but good if we're not. Phase 2 has statues to block incoming projectiles. And both of these stages allow for very quick stocks when you land Flying Slam. Battlefield adds verticality to your attempts at zone breaking, and villager prefers to keep you at a horizontal position.
I never labbed it, but I know Villager's throws are weight based. I suspect there are still some true combos at very low percent out of Dthrow, like jab, but at mid and late percents, absolutely Double jump as soon as you can to avoid Fair. You can even counter that with a Dair since he's always at point blank range, just don't do that if you're offstage. When you're recovering with fortress, you can't afford to travel straight up into Fsmashes. Get to the ledge diagonally and hope it doesn't clip you during ledge vulnerability. The more horizontal to the ledge you are when ledge snapping, the higher chance of you not having any vulnerability frames at all. And finally, if he's ever forced to use Balloon Trip to recover, don't let him back for free.
