For the most part, my fears were unjustified. My friends are well aware of my personality and while that may be amplied in high-stress situations, they seemed to be fine with me for the most part. However this list below is something that I have experienced first hand while traveling. Check it out:
1. Budgets Don't Match-
Easiest solution is to just have the frank discussion. Set limits and decide what you would be willing to splurge on and what you'd like to hold back on.
2. Your Planning Styles Don't Match-
Let everyone be as much a part of it as they want to! The solution I've finally worked out for my crew is for everyone to write out a top 5 musts and then build an itinery from that.
3. Dining Tastes Don't Match-
Basically it comes to which would you rather have: complaining and multiple bathroom breaks OR a balance to unique and safe. With food you can't push people, they systems might not handle the change well. That being said, there is no reason to live of MacDonald and KFC the whole trip!
4. Conflicting Sleeping Habits-
Schedules help to force this lazybones out of bed and keep those early risers from complaining about having to wait.
5. Opposite Activity Levels-
Again a top 5 list will help you balance these.
6. Extroverts vs. Introverts-
Be respectful to your introverts, but don't let a great connect slip by!
7. You're Not Both Road-Warriors-
Have this discussion when making the itinery, as well as the sleep schedule discussion. They go hand in hand.
8. Dissimilar Interests-
That top 5 list will sort all of that!
9. Your views on tourist attractions vary-
Balance. Also, some things can't be missed! I hate the Eiffle tower, but I definitely have a photo of me "climbing" it through corny forced perspective! Some cheesy is a good thing ;)
10. One of you loves the nightlife the other prefers a quiet night at the resort-
Agree that this will not be a nightly event. There's a balancing act and if you're dealing with opposite personalities you have probably had this discussion before on a Friday night a home! Use those interactions as a good base for your planning.
So even though I have experience almost every one of these and they were very challenging, I want to STRESS to you that nothing is more important than experiencing something completely new with your friends! Just go into your tip knowing that things might be rough, but they'll definitely be worth it.