Thailand: Choosing a Route

Hello Wonderful People!

I'm going back to Thailand and I literally can't contain my excitement! I'll be jetting off to Bangkok in October, for a 12-day whistle stop tour of the country. It's going to be amazing tip, but going back to Thailand after my last visit over 2 years ago, is going to be very bizarre. I think my travel bug is going to be reignited! I'm jetting off with 7 of my best mates and we are currently facing a major dilemma: where shall we head to make the most of our trip? We want to see Bangkok and go island hopping, but with only 12 days to fit everything in, we have to stick to a strict route. I'm not normally a fan of following an itinerary when travelling, it can detract from the spontaneity and sense of adventure. However, in this case I'm willing to let it slide, as we want to see and do as much as possible in the short time we have. We have come up with 2 possible routes to take on our trip, but the real problem is deciding which one to take?

Itinerary one:

Day 1: We land in Bangkok on a Thursday evening, so heading to the hostel and freshening up will be our first priority, before heading to the backpacker mecca that is Khaosan Road. Grabbing some food then hitting the bars is top of the list for our first night in Bangkok. I literally can not wait for the madness!
Day 2: Exploring Bangkok is a top priority for day 2. Last time I was there I never got the chance to check out the floating market, so I'd love to do that! It would also be cool to visit some of the temples and get a tuk tuk round the city. Heading to the famous Sky Bar would be a great way to spend the evening, then possibly heading back to Khaosan Road to end our night.
Day 3: A lie in to cure our inevitable hangovers will be needed, before we do a final bit of exploring in the Thai capital. We would then catch a night train from Bangkok to Chumpon, so we can hop on the early boat to Koh Tao the following morning.
Day 4: Take a morning ferry to Koh Tao and check into a hostel. Hopefully the weather will be nice and we can have a chilled day on the beach. After a day of soaking up the rays, we will head out for a nice meal and check out the islands nightlife.
Day 5: Exploring the island in the morning to find some nice beaches would be a nice start to the day. The rest of our time can then be spent relaxing in the sun, Chang beer in hand. Another meal out and a few drinks will be a nice way to spend the evening, and if we aren't too exhausted another night out could be tempting!
Day 6: Check out of our hostel and get a morning boat to Koh Phangan. Head to Haad Rin, as this is the place to be for any Full Moon party and check into a hostel. I'd like to do some exploring of the island, as the last time I was here I didn't really leave the close proximity of Haad Rin. As the Full Moon Party is the following evening, I think the best idea would be to have a nice meal out and a chilled night in the hostel. This is the sensible thing to do, if it actually happens though is another thing all together.
Day 7: FULL MOON PARTY!! Chilling out in the morning, in preparation for the crazy night ahead is essential.
Day 8: Spend the majority of the day recovering from the Full Moon Party; hopefully on the beach if the weather is good! Get a late afternoon boat over to Koh Samui. Treat ourselves to a nice hotel to enjoy the last few days of our holiday in luxury!
Day 9: Chill out, relax, do some more chilling, have lunch, go to the beach to relax, go back to the pool to chill, go out for dinner, have some drinks. Done. This is a day dedicated to doing nothing!
Day 10: Spend the morning chilling out and making the most of the (fingers crossed) nice weather. Get an afternoon flight to Bangkok.. SOB the holiday is nearly over :( We will probably have to stay in a hotel near the airport, as we'll have to be at the airport super early! Which means no last minute Bangkok adventures for us!
Day 11: Up early for a flight back home. DON'T MAKE ME LEAVE :(

Itinerary two:

Day 1 - 3: See above. We would still have a few days and nights out in Bangkok to being outrThai adventure! However, during the afternoon of day 3 we would catch a flight down to Phuket and settle into a hostel there for the evening.
Day 4: Explore Phuket!! The weather will dictate the majority of what we do - if it's hot and sunny we will hit the beach. If a monsoon hits, we'll be looking for an activity to keep us occupied! Checking out the Big Buddha or wandering round Phuket old town would be top of the list. Then a night out is obviously on the cards!
Day 5: It would be nice to head to the beach in the morning to chill out for a bit and then do a touristy activity in the afternoon. I know a few of my friends would love to ride an elephant, so they will be dying to do that! I've been lucky enough to experience this twice, so I'd love to do something like a Thai cookery class!
Day 6: We would get a morning boat to Koh Phi Phi and check into a hostel. Checking out the local area will probably take up most of the day before we go out for an evening meal and some drinks.
Day 7: A trip to the iconic beach, where the film 'The Beach' is set is an absolute must when visiting Phi Phi. I just really hope the weather is nice!
Day 8: Sleeping off our hangovers and chilling on the beach (seems to be a common theme on this holiday) will be the best way to spend the day, before catching an evening ferry to Koh Lanta. Checking into a nice hotel will be a nice way to end the holiday with a bit of luxury.
Day 9: Making the most of our hotel and popping to the beach will be the main plan for the day. Going for an explore of the local area and a nice meal in the evening will also be on the cards.
Day 10: We would have to be up reasonably early to make our way to Krabi for our final journey back to Bangkok. Having a little wander round and lunch in Krabi would be ideal, before heading to the airport to catch a late afternoon flight. Again, as in the first itinerary, we will have to stay close to the airport, thanks to an early flight, so I doubt many Bangkok adventures will happen. I refuse to rule it out though!
Day11: Up early for a flight back home. DON'T MAKE ME LEAVE :(

So the real question is; which coast to go for, east or west? Which itinerary would you choose?