You should be able to upgrade to a FSA SLK without any troubles so long as it's BB30.
If it's a 386EVO or the new 392EVO, then you'll need to proper spacer kit accordingly to adjust for the increased size of those spindles. You can contact FSA via support any time and ask if they can direct you to the specific product (in that event).
Additionally, you'll want to get a new press fit bottom bracket for the fresh bearings.
Upgrading the groupset is going to be money. 10 speed Road for Shimano sees Tiagra as the cheapest groupset, and that's not saying much. New shifters will set you back about $200+ even if you get a deal.
Maybe shoot for a 10 speed Campagnolo set instead, such as Veloce or Centaur. The carbon Centaur cranks have been seen for just $130! And the alloy ones are like $65! You will need to get a Power Torque bottom bracket for that crank though. They do make them in press fit luckily.
Knowing this is an old thread and the OP likely has forgotten about it, it still merits response. Had the bike been mine the drive train replacement would certainly be Campagnolo either 10 or 11 speed. The crank remains the same as it is an OK crank.