what do you mean by lag? while creating the theme? or do you mean when using the theme on the phone? I guess if it's on the phone it'll actually depend on the size of the theme and/or if it's animated. Normally those factors do tend to weigh on the lag issue from my own experiences. I would reduce the animation to a low and keep it as simple as possible and friendlier. Second, I would create enough space for my unread icons to show all when they come in. I hope this is sort of what you were referring to; if not I guess I was wrong lol. This is the only bs answer I could come up with. Sorry I failed you
What's the matter? CIA's got you pushing too many pencils?