What's the goal of the game though? The reason games like LoL are fun is because they're so fast-paced. You don't have that pace in RSC or even the current Runescape as it's just point and click. So there needs to be something worth playing for to give the game replay value.
Your account would start at level 3 and with 1k gold you can buy any thing up to iron til you're in level 5 combat skills. Steel and so on and so on from a shop at your side of the map.
Exp for the mini game would be x5 for the first 5mins then x30 etc till FLATS so you'd level super fast.
Have chicken run from one side to the other for the first 5mins. (drops gold,bones for pray)
Then level 13 wizards and level 18 thugs (wiz drop runes,bones,gold) (thugs arrows,bones,gold) for 5mins.
Next guards run for the next 10mins. (more gold)
(more monsters after)you don't lose items when you die and there's only lobs for free sword fish would cost GP.
Have a black dragon on 1 side of the map and a blue dragon on the other side. (both drop dragon meds/longs/battle) thats the only way to get those items.
A Kings black dragon at your base that the apposing team has to kill.
Just some thoughts on it.