Egregoros

Any gas mower at your local big box store will work fine for a couple years. Better brands will hold up better and last longer, etc. It's a little hard to keep up with brands because good brands of the past fall victim to getting purchased by a conglomerate and enshitification.

All of the gas engines are likely to have carburator issues, problems starting, etc, after a year or two unless you are careful not to leave old gas in them.

Plug in electric sucks, low power and the cord is always in the way.

Good, not cheap, battery powered mowers work pretty well. Less maintenance and quieter if that's important to you. They will cost more than an equivalent gas mower. The cheaper ones are trash.

Mulching/ bagging/side discharge depends on how you manage your yard. If you mow frequently and don't allow the grass to grow much in between, I prefer the mulching as you don't have to handle the clippings and there's not a side chute sticking out and spraying clippings. Bagging works if you want to compost and don't let the grass get too tall, otherwise your bag is filling up constantly. Side discharge is best otherwise, and you just have to rake if your grass is so tall you're leaving rows of clippings.