Conflicted

So I've been writing a bit in both of my most active stories (Main Attraction and Invaded by Twilight Sparkle). This is a good thing, yes? No...no it isn't. I'm absolutely terrible at multi-tasking, so I've been thinking...Maybe I should focus on one or the other? I love writing in both, but I definitely write MA more fluidly. I suppose it's because I'm not very good with writing combat...which is everything in Invaded by Twilight Sparkle (but it's Twi-abuse, so it's all good). I guess I should just up and say it. If I were to focus on just one of those stories, which should it be? Of course I'm still going to write in the other(s) (I didn't forget about Signature Heroes), but I figure having a primary story would be a good thing.