Symptomatic that perhaps the mod is trying to do too much VTOL wise.

In the base game, I would understand, that is the behavior indicative of the vanilla game, control surfaces tied to vectoring, super sensitive, sometimes wildly erratic, throttle adjustments. Throttle goes way up, which + is responsive at least, but ---, decrease the throttle, sinks like a brick.

I have VTOL loaded, which in theory, solves that issue. Run that, for instance, with Project Lightning F-35B, the vectoring works fabulously. SVTOL take offs landings really superb.

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=924553546

So I'm not sure what the gap is there, but needs work, either way.