My only real problem with the game is that just doing mission content is not enough. Got to level 25 and it seems like the enemies were getting harder and harder due to me hitting the minimum level for missions and having more than one tough npc in groups. Did a mission at level 24 and the mobs were at level 29 with 4 lieutenants and one of them kept on summoning zombies. Considering that there is supposed to be an XP boost going on for beta, then it is going to be a serious problem for people that just solo. The potion spam necessary to keep myself alive was too much in those situations even with a Cleric companion.
There is also the problem that you have to send away your companion to be trained and it takes about an hour to train them. Also looked at the prices at the C-Store and it looks like about $40 for the best mounts. Saw an Armored Howler for 4000 Zen which looks like a real nice and nasty mount. At least with STO, we get an operational mount that has numerous interesting abilities for about that price.