It would be good to have the option too trade in lower rank exploration awards for high ones (at a suitable ratio 2:1 for example) especially as you are likely to have enough to buy some useful items just as you reach the next tier. With PvP merits there is no such problem, though I accept that in PvP you are always basically facing equivalent enemies. So the option to trade in unused/saved lower Tier awards for Award points of your current Tier isn't unreasonable.