I almost bought the Agent Rocker 1-2 years ago after trying one, so here is my 2 cents:
From what you are describing it makes no sense to get another board unless it is a dedicated park or pow/freeride board. The Rome is super versatile and should cover your all-mountain and general park needs easily, probably better than a Machete or Proto (I also looked at those).
And why do you think the 159 is too long? At your weight it sounds about perfect - I weight 25-30lbs less and would have gone with the 157 for myself. 159 also has more edge hold for the icy stuff.