A lot of good points there.

MHTK is really interesting, given the small size and active radar seeker.  It's even been proposed in a multi-shot pod suitable for man-portable use.

It might be interesting to see a family of systems approach -- a small interceptor like MHTK for killing Class 1-2 UAS loaded into a multi-round canister that would be interchangeable with a larger single-shot MANPADS that is more of a Stinger replacement for engaging helicopters, low-flying fixed-wing aircraft, and low-flying Class 3 UAS.  If it is interchangeable with Javelin, so much the better.  Your dedicated air defense launchers can be useful even in a lower air threat environment and your ATGM teams can become a  supplemental air defense threat if need be.

In terms of the direct Stinger replacement, adopting some sort of dual-mode seeker (IR/UV plus MHTK-style radar) seems like it would improve countermeasures resistance.  And then yes, anything you can to to improve kinematics out of the tube would be good.

US is buying more Stingers as a supplement until a 'next gen' system is developed:

https://www.reuters.com/business/aerospace-defense/exclusive-us-army-replenishes-stinger-missiles-after-ukraine-shipments-2022-05-27/