I stopped using dressings. I have a two bottles, one for float, one for sink. They are intended for flies but occasionally I have used them to dress my leader/tippet. Sometimes I would actually put sink on the leader to have my tippet break the surface film on still waters to avoid the coiling tippet shadows on the surface.
Thing is, I have noticed that both float and sink leave an oily stain on the water surface. Doesn't look too nice. I am not exactly sure what is in the stuff but it looks oily. I basically stopped using either, I figure I don't need to put anymore stuff in the water.
Keeping your floating line clean, ie; give it wash with a very mild soapy water. will make it last longer and float better. (I would avoid scotchgard, armour all, etc. you may very well void your warranty.)
You might try using flies that are a little more 'floaty' (Tom Thumb) even try some flies incorporating foam in them (foam body ants for eg.)
Also keep a couple of each fly handy, and as one is totally soaked, switch it up to a dry version, and let the soaked one dry out on your drying pad, repeat.