Probably they should:
-give rewards (gold, random weapons, item, etc.) for leveling up.
-put level requirements for quests. This would encourage people to level up. For those who do not reach requirement, give them alternate quests.
-provide lots of places (asteroids, another city on the same planet, etc.) to fight and get random items like DF.
-categorise inventories. That is to say something like, you can keep up to 20 misc. items(badges, quest items or keys, etc.), 5 energy blades, 30 mechas, 30 mecha weapons, etc.
-inter-game benefits(aside from Verified items). e.g. You play Dragonfable, you get items on Mechquest or AQ and vice versa OR you get extra starting gold OR etc.
-(said and promised)better energy blade fight system! Also, I would like to add that the MQ team might want to sell items that boost human HP or EP like armour. and provide a separate leveling system for character.
-keyboard controls. Instead of using only the mouse, MQ may utilise the keyboard to control fights and movements.
-better and varied sounds. MQ's current collection of sound effects are good but can be made better and clearer.
And oh BTW, I object that SCMM should be made non-rare. They should pull players to upgrade to SCs.