Zoltan, Thanks! Yes, in RF, just about everything is a compromise. And, yes, size, power consumption, noise, spurious products, etc. are all a problem.
The beauty of moRFeus combines three building blocks that are often together: 1) LO synthesizer, 2) Mixer and 3) Controller.
BTW, here’s why I was asking if the LO could be swept:
The Fundamentals Of Spectrum Analysis
Keysight Technologies - Spectrum Analysis Basics
How much of the back-end can be done with a Software Defined Radio? GNU Radio?
How about one that has a narrow filter, a high gain LNA in front of it? What can you do with an SDRx and a few more components available on E-bay? Is the IF filter narrow enough?