Regarding the planetary commendation vendors on fleet. IMO the mod vendor for each planet should have just one of each type of mod in their inventory, it's level requirement on the high end of the recommended level of the planet they're acquired on. ie Tatooine is 24-28, so all mods are level 27; Voss is 44-47, so all mods are level 47.
There would be one of each armouring, barrel/hilt and mod for Strength, Willpower and Aim and their endurance-heavy counterparts, as well as the Skill type for Cunning classes (unless people actually use Patron, then those as well). There would also be a variety of enhancements for tanking and dps/healing. This way there will be an even amount of mods for all classes/specs without the vendor having to sell a huge number of mods total.
Currently at some vendors there are certain mods that are 2-4 levels below the highest level mods from the same vendor, or none at all for some types. The comm vendor favours the mods that are towards the top of the list when sorting by name, and the mods toward the bottom of the vendor window are lacking. There are many mods for Commando/Guardian/Force Wielder while Might/Resolve/Skill/Reflex at times have none at all.