Hello,
Is it the front sight you can't focus on? Too small?
If you need a bigger front sight then XS is the way to go. I think even their standard dot is bigger than a average front sight post. I doubt you'll be dotting you I's with them, but I suppose if you practice enough and learn the point of impact you might be able to make precise shots.
Also take a look at Novak's ghost ring sights. I've really been wanting to buy a set of those mammajammas. I beleive it was a border patrol member who told me that his group used those sights and saw no difference in accuracy between those and standard sights within 25 yards.
Theres also a trapezoid sight set that might help you out, but I can't remember who makes them. Try a search engine. Wait, here ya' go. I think these are it. Advantage tactical sights
ATS They look friggin' HUGE though
Take care and eat your carrots