So, I went to my local Sam Ash and believe it or not, they had some Renaissance heads I was able to scope out. To add what you guys have mentioned...they didn't seem that they'd be very warm or calf-like in sound. They were almost transparent looking...but might make some good reso heads, though.
I was also able to check out a Skyntone head, and it did seem like a good alternative to calf. I bought the 14" they had, so I'm gonna try it out on my snare.
I agree that the Aquarian Vintage heads don't sound or act like calf at all, which is why I don't care for them.
As for the Remo Vintage Ambassador heads...I love 'em! I have a set on my 2006 Ludwig Classic Maple kit with clear Ambassador resos, which makes for the best combo of heads I've tried on that kit.
I think I'm gonna try the Skyntones as battes and Renaissance heads as resos on my '49 Leedy kit. I'm thinking that might be the winning combo. Thanks for the replies, Fellas!