Try changing the resonant head - maybe it's worn out. Those are one of the most neglected items on the drum kit. Also, there is a 'magic tuning rod' that could drastically alter the tone fro your drum. Once you mess with that one (or two), you're going to be in for a long day, lol! You could try a G1, but I would say to experiment with the batters also. Maybe the batter head is not the head for those drums. We often try to force fit some heads, mostly to follow the status quo or for mostly cosmetic purposes (just to match).
For example, I have an 8" tom at church, and I use a REMO Ambassador on the batter and the resonant side. This is done for the most sustain for that small drum. IMO, I feel that a two-ply on that sized drum does not allow it to speak as freely as it should (if you're going for a open and full tone). On the 10" and 14", I use REMO's Smooth White Emperor, which gives is the sound that is in between a coated and a clear head. For the resonant side, I use REMO's Ambassador clear.
Although it's not aesthetically pleasing (to the eyes), it produces the desired tones that I want to hear from the toms. I say just go wild and experiment and find the sound that you're after.