First of all, yes. You don't need to spend money to have fun (Unless you're talking about In-Game Currency)
Second of all, always bring an Antidote and Burn Heal with you wherever you go. The chat is usually always active (Global) with a few moments when it goes silence then goes active again, the community is kinda nice in some points if we don't have the trolls online or if the trolls are afk or if the trolls are muted or if the trolls aren't up for trolling. The kind part of the community answers your question while the troll part of the community doesn't answer your question but if they do, you'd get a half-assed answer. Anyways, it's the community that makes this game fun so you shouldn't worry about it.
Now lastly, yes. Since PokeMMO is a literal grinding game, it gets more rewarding the more you play it daily. The more active you get, the more munies u get. The more munies u get, the better pokemans u get. The better pokemans u have, the more events u can join. That's basically about it.
btw... Welcome to PokeMMO :D