<human>: Greetings and sorry for such a long post,

I am sure that this has all been hashed over many times in this sub and with a bit of searching and a little luck I could undoubtedly find the answers to all of my questions, but here we go anyways... We are planning our honeymoon trip for next year, probably around September or October (2016), as of right now we know that we will have a 7 day stay in Koh Samui (my parents are gifting us their Hilton Grand Vacation suite as a honeymoon gift), we will however be in country for 12-14 days and have yet to make any plans for the remainder of the time. 

For me, I would like a mix of off the beaten path/tourist fun.  For my wife to-be, she would almost certainly prefer a 14 day spa/beach session but she's excited to try new things as well (it is also the first time she will be leaving the country (USA) and she is understandably a bit nervous and incredibly excited).

* We were thinking of flying in to Bangkok and spending a couple days there.  Can you recommend any activities? Can we go to a Muay Thai fight? 
* We love to hike and would really like to spend a couple days taking in the beauty of the country as well.  How easy is this to do as far as getting to where we need to be? Are there any recommended must see hikes/attractions? Any cool temples or anything like that? 
* We absolutely love Thai food (one of the reasons we have decided on Thailand in the first place).  Beyond any recommendations for amazing food to eat, are there any other places of cultural significance in relation to the cuisine? I have heard of Samui Institute of Thai Culinary Arts and will be checking that out, any others? 
* Before I get into this one I would like to say that I understand DO NOT DO DRUGS IN THAILAND... However, whats up with the mushroom shakes or spliffs I have seen on what appear to be some local menus?

Really just looking for any recommendations as we are just starting to plan. Thank you all for your suggestions, help, and recommendations in advance it is greatly appreciated.

Can you provide a brief rundown of the text in within 3 sentences?
<bot>: Looking for some really cool shit to do before arriving in Koh Samui as well as while we are there.  Would love hiking recommendations as well as anything of cultural significance. What's up with the mushroom shakes? Thanks!