I did a little digging at the excellent Encyclopedia Astronautica website looking for info on the Zenit booster. One possibility is to develop a full-sized version of the BOR-4 spaceplane and launch it on the Zenit. The Zenit can put about twice the payload into LEO that a Soyuz booster can lift. That would allow for either an overgrown Soyuz with payload compartment like I mentioned in my previous post or perhaps a spaceplane that could be reused. A BOR-4 model was used by NASA to help design the HL-20 (CRV). I see potential with this idea. Of course, the Zenit's reliability would have to be better than 80%, but many of those failures happened in the early phases of the vehicle.

It appears the Zenit might have been used to launch a spaceplane called Uragan. If true, this means the vehicle is capable of launching a lifting-body vehicle.

http://www.astronautix.com/craft/bor4.htm
http://www.astronautix.com/lvs/soya511m.htm
http://www.astronautix.com/lvs/zenit2.htm
http://www.astronautix.com/craft/uraeptor.htm

I think the Russians could go either way with these ideas. An enlarged Soyuz capsule capable of carrying perhaps 5-7 people and a payload module could be very useful. Not only would it reduce the number of launches required to support their ministation and the ISS, the larger passenger capacity could reduce the need for the CRV. On the other hand, a reusable space plane would have higher development costs but could have lower operational costs. I agree that the Russians have the engineering talent to produce either of these ideas. The problem, as always, is money.