You can vary it up, I can't think of a single skill that isn't at leasta little useful, and all trees have a wide variety of useful abilities. Some shine more then others, like windmill and smash, but there's nothing wrong with ranking up other stuff after you've got them up to speed. Or even before, the combat is very much skill based, and as long as you know when to use what skills you'll prolly end up okay.
I honestly like a lot of the equips in this game visually, so I think it's fine. But if you start with something you dislike, there are things called robes which cover your active slots, and provide an alternative. They also have hoods you can bring up and down if you wanna keep your hairstyle or whatever visible. Humans and elves have some nice cheap heavy armor if that's your thing, giants are a bit more restricted in all equip senses. I'd say they're the worst off as far as good looking stuff goes, but don't be afraid to look through the mabinoger wiki, even if they don't have a ton of pictures up.
Bards are viable, but you really can't be a "pure" bard. In a huge party, people can protect you fine, but when a fight breaks out in a small party, you'll probably be expected to defend yourself unless you're rolling with a tiny god. I'd look into a "combat" skillset, and at least learn how it works, again, you don't need to heavily invest into a tree, most of your efficiency will come from just knowing how it works, and maybe periodically boosting a particular skill or two, while you focus on bard as your "main".
I also again feel the need, for whatever reason, to say it's very hard to mess up your character permanantly. Or at all, really. So don't stress out too much over where your AP should go, but if you have any questions, go ahead and ask people, they're friendly folks.