That doesn't look like Baikonur, Plesetsk or Vostoshny...Added Stage 3 (remember, russians count boosters as "stage 1"). The engine is a brand new "RD-0150", not a lot of details about it on the Web but that's an high-performance LOX/LH2 twin chambered engine (Kosberg).
Of course this is a "paper rocket" so we have no flight profile, but I guess that stage is similar to the SaturnV SIVB : it will finish the insertion in parking orbit and re-ignite to perform the TLI.
No here I'm at KSC because I wanted to be sure I had a flat surface to launch from...That doesn't look like Baikonur, Plesetsk or Vostoshny...
The Energia-5VR architecture offered obvious advantages over the Energia-5V: namely, it was shorter and lighter, while carrying practically the same cargo. Moreover, because it consisted of only three stages, rather than the four stages making up the 5V variant, the 5VR version would likely be cheaper and more reliable. During a lunar mission, the third stage of Energia-5VR would fire twice: first to accelerate the payload to nearly orbital velocity and then to deliver it into a highly elliptical orbit with an apogee of 35,000 kilometers. Once there, the crew of the PTK spacecraft could check all onboard systems and, if everything had gone according to plan, the spacecraft would fire its MOB-DM space tug to enter an Earth-escape trajectory toward the Moon.
In contrast, Energia-5V would use its third stage to enter an initial parking orbit and after its separation, the fourth stage would accelerate its payload on an Earth-escape trajectory.
"...the difference being one-plane gimballing in the RD-170 used in the Energia launch vehicle strap-ons versus two-plane gimballing in the RD-171 used on the first stage of the Zenit launch vehicle."
The chambers of the RD-170 engine as part of Block A of the Energia rocket swing in two planes: in the radial plane passing through the longitudinal axis of the engine and the chamber axis, and in the tangential plane perpendicular to it. Such a control scheme is more effective in the structure of the Energia rocket package, but it requires more powerful steering gears that overcome the load created by the oncoming aerodynamic flow on the protruding part of the combustion chamber nozzle beyond the parameter of the external bypass of the block when it is deflected in the radial direction.
The combustion chambers of the RD-171 engine of the first stage of "Zenith" are deflected when controlled only in the tangential rolling plane. The nozzles of the chambers do not enter the aerodynamic flow around the stage and do not experience its load. Steering gears are significantly less powerful. The control efficiency of this option is sufficient for the Zenith missile.
As for reusing meshes, I'd say only do it if they are big, otherwise it will be too much work for little (or no) gain. It makes sense to have each booster using the same mesh (you probably do that already)
I'm curious: Is the Energia-5V rocket the same as the Soyuz-5/Irtysh rocket or they are different?