Not sure how the game is currently doing but RS used to be one of my main games decade ago. You don't have any certain path to choose. You can just do what you want at any given point and it has a huge variety of activities which most importantly are fun!

The grinding is afkable if you want to grind but I doubt it's neccessary. You level up just finding out new things and playing the game. What I absolutely recommend is doing the quests! They are the best in mmorpg genre and nothing like kill x wolves and bring me x amount meat.

What I really enjoyed was miniganes as well but honestly, I can't tell if they are still popular and alive. I quit after maxing and "beating the game" when I didn't find anyone playing those minigames anymore.

Aside from that, I can't but recommend trying it out and don't feel forced to spend any money on MTX. You don't gain any real benefits from them but considering buying cosmetics if you really like them and are okay with spending money on mtx (most people were very against that almost a decade ago before fortnite and such mtx store games became popular). Treasure hunter (or whatever gambling machine name it had..), don't use that except for daily free spins. It's useless and truly gives nothing useful so leave that alone.