One such thing I am working on is improving my hand strength on my left hand so I can do better finger work like hammer ons, flick offs, and of course more advanced chords (barre chords). Coincidentally I put heavy gauge strings on my acoustic recently for slide guitar playing. The sustain on notes and ability to generate vibrato is much better.
The flip side of heavy gauge strings is that they are harder to hold down. Way harder.
My playing skill has dropped with the recent change to heavy strings since I am finding it harder to hold down the chords as I play. This is a temporary setup on the road to stronger fingers and the ability to switch from chord playing with fingers to slide playing with uses less chorded notes.
So, if you've been playing for several months on light strings and can hold your chords easily but are looking to strengthen your fingers you could try starting to move up in thickness with your strings. I would recommend moving up to medium gauge for a while before making the leap straight to heavy.
Here is more technical info and charts on various strings gauges for guitars: Wikipedia String (music) Guitar