I spent valor points on my items so that I would get my ilvl up and be accepted in groups. Of course better items dropped along the way and now guess what, I can’t upgrade them because I have little valor points left and it’s capped. Conquest points allow you to buy the exact piece of gear that you want and you are in no danger of getting a better pvp gear drop.
I too think the system is flawed, if anything I would put a weekly cap on what can be spent, but not a cap on the amount you can acquire total. Beside there is already a system in place, to upgrade the gear you need to complete all dungeons lvl 5, 10, 15… so why the cap?