Re: Casting dilemma
Fans of UL tackle (including me to varying degrees) will tell you that good casting technique will overcome quite a lot and I regularly fish small woolly buggers and my own minnow patterns on a 3-weight. However, I'm using fairly large leader material vs. the "norm" for a 3-weight (usually 4-6 pound mono) and the leaders are short (6-7').
Heavier fly line will help you a lot, regardless of technique. A 5 or 6-weight will probably be ridiculously more simple to cast for you.