TTIP is more to do with the power of corporate interests than the EU specifically, IMO. Particularly under a Tory government, the UK would probably be a willing participant anyway. It's a bit disingenuous to call it a problem with Europe. Of course if the EU and the USA didn't exist, they couldn't make this agreement.
I'm reluctant to get into another politics thread, but I'm pro-EU and would vote to stay in. I would be gutted to be part of a country that considers itself so separate from its neighbours. There are legitimate concerns about democracy to a certain extent, but I think they are way overblown.
I'm also in favour of freedom of movement, an immense benefit that people in the UK tend not to take advantage of because of language issues etc. Being able to move and work freely all over Europe is amazing.
Everything is global now, people are tied more and more closely together in all sorts of ways. I just think it would be a massive backward step to pull out of a union like this.
I don't have many economic arguments and all that TBH, my feeling is more a point of principle about internationalism and close partnerships.