Armor searching is pretty easy. Just set it to "Armor" and then the class (heavy, medium, light or adaptive). You can search like that no problem or you can set it to search specifics (helm, chest, etc). Maybe you have a character in the name field?
The only real things I'll comment on is to not buy gear with credits. You should keep well enough geared via quest rewards and commendations. As for spending commendations - thats what they are for. Upgrade your gear first, then your companion's if you have enough and they are worth while items.
You don't "suffer", you just get the standard XP instead of a boosted XP.
Clever players realize that rested XP doesn't make a difference to mission/quest rewards and only effects XP gained from killing mobs/enemies.
[edit]Subs[/edit] actually are getting a slightly higher amount of XP than before. When the "who gets what" page says that F2P get less XP they mean than subs. [edit]F2P players[/edit] are the new "100%" rate, which subs used to have.
The thing is is that it is you and not the F2P model. Up until P2P launched all players were getting XP at the same rate you are now. With the launch of F2P people who sub get extra XP. So there was almost a year of people with no leveling problems.