I like that idea of breaking the job up. Seems like the heat shield could have been it's own seperate launch that just provides the platform, and a bigger/better one, that the scope comes along later and attaches to.

Maybe the main reflectors could be like that too. One or more packages that are just the reflector, maybe not even all of it but just sections.

I think the adjustable array of smaller sections is simply necessary to get and maintain the focus anyway, so the adjustability is not an expensive extra.

Hubble actually went up with a botched main reflector and couldn't be corrected directly. The replacement secondary optics was only a terrible patch, and really only even possible because the scope is within human reachable space to do that level of heart surgury in-situ like that.

So if the reflector has to be adjustable anyway just to work at all, then it's not a crazy extra fundamentally, and only a bit extra to have the pieces be able to be shipped individually and self-assemble on site. The inherent adjustability which was required anyway, allows for the inherent inaccuracy of connecting two parts vs one solid part.

With 2 or 3 or more smaller component missions, each project becomes not only less critical and more tolerable of a failure, but also less complex and less likely to suffer a failure.

And it seems like this project does have at least 2 or 3 natural major building block boundaries. The shield vs everything else is one for sure. That could be turned into a platform, maybe for more than one instrument added or replaced over time, and could maybe supply power as well.

Then maybe also the main reflector vs the actual instruments. And the main reflector itself could be in simpler discrete sections instead of having to fold and unfold.