It doesn't matter. Ship upgrades affect how easy or hard it is to do space missions. Higher level space gear needs to be earned though commendations or crafting, not by spending real money.
And yes. yes you did.
Custom mod gear - think like an almost look alike Darth Vader out fit, a luke/han ect ect outfit
Mounts, a mount that scales with your riding skill
pets, lost and lots and lots and lots of pets.
Space ship upgrades, grade 7-8-9 ect ect, or custom skins for your ship.
If this gear has no mod slots, Sure. Let people buy it with real money. If it has mod slots, make them earn it ingame.
I'm not nerd raging. I'm stating a simple fact. If it happens, I'm gone and I doubt I'm the only one. Cash shops ruin games. Force knows I'd even go as far as saying it ruined WoW.