You realise the current stuff is added step by step but you can choose the order once its finished?
Your most wanted chara may be in the next or in the last update of the current eventwall, dunno if neko has a fixed order in mind or just adds the groups with the most ideas for suitable content first. However, once that groupscreen is filled its your choice who you want to play first...unless you play each update like most of us, then you have to live with the release order.
For example, i would have picked the current group last...not because i dont like them, i just always start with the lolis ^^