SNAT and NAT on difference vlans

First off, thank you for your assistance with this -- I really appreciate the time you're taking to respond.

I think I'm confusing myself though -- the above irule assumes everything coming through that wildcard virtual-server will only ever use a traditional SNAT. What if some of the source servers need a 1:1 snat? Does this have to become one giant monolithic irule, where every case specific case is handled in an elseif clause? Or would you then create more source-specific virtual servers for anything that needed a 1:1 SNAT on any of the interfaces?