I remember people having issues with gear, if a new player it might be an issue but if you have cash just use the GTN/Auction. This was a long time ago though when they did that, not sure about it now.
They give you way more commendations than you need to keep geared now, plus you usually end up outleveling mobs anyway.
I'd recommend a few cartel coins on the consumable xp boosts also, they count for the 12x
No need, you get XP boosts as quest rewards and if used sensibly last all the way through.