Every big patch there is gear reset. Though it is not exactly reset - just new, higher level gear is introduced with higher stats. Usually new greens are better than old relics.
Considering Epics will be out soon, how will that affect our gears again? Will they be reset to greens? Would we continue with them as they are and proceed to epic upgrades?
It wont affect gear in your possession at all. Some pieces will need new crafting new scroll to upgrade them to epics. Other (those without yellow arrows in upper corner) will need to be crafted with profession or dropped from boxes.
Additional effects of unlocking epics will be changing starter gear box in academy to green 110, drop in Al Rihat will be upgraded to blue. This upgrade by 1 step up will happen with each next astral sector/gear quality unlocked.
When players start finishing relic quality gear there will be time for next big patch, new level cap next gear "reset" - higher level with better stats so ppl will need to start gearing again.
About investments - all crafting resources are from game and can't be used for anything other. Paying for lootable gear will speed up collecting those pieces by 2-4 weeks. Though if you actively rush astral sectors you can get all those pieces first day with some luck... or stack enough embrium from plundering mazes and you will be able to buy them from personal allod.