Benefits depending on guilds level when with regards to lower taxes, extra battle points and XP etc.
Good guilds will give you advice and knowledge of the game and improve you as a player.
They will also host events and games etc for you to compete in and gain extra cards and clintz.
Asca founder of a guild I see now point in being in the game and not being in a guild. I think it is essential if you want to experience all the game has to offer.
All you can do is give it a try. As long as your not an A-hole you will be fine. If you are an A-Hole I suggest staying away from me, Babs and Merlin. We love A-Holes, they give us the chance to get the turkey baster and hot chilli oil out.