Yes, I've also noticed that but I agree with you that it's good with some variety. Although, in the end I think the most important thing is to do the things you love the most :)

That's a good question! If you want to stay here for a longer period of time then I recommend you to apply for a 60-days tourist visa multiple-entry. In this way, you can stay here in Thailand for 60 days, leave Thailand (go over the boarder), then entry Thailand again. With this visa you are allowed 2 entries in Thailand.

Another way is to become a student here in Thailand, eg. start learning thai.

Take care! :)