Interesting discussion.
It strikes me as too bad that Finale really seems to have very little interest in optimizing their program for use with non-Garritan libraries. I bought Dorico this year, but am still using Finale as Dorico (2.0) still has some major issues for me (no swing feel; limited control of velocity, even though they have a piano-roll editor).
In Finale, I've managed to have a lot of success using keyboard maestro (I'm sure any other keyboard shortcut prog. would work) in combination with the midi tool. I have various macros programmed to adjust velocity, y axis, slot crossfade etc. It can be pretty quick when it's working - unfortunately their visual feedback (Finale's) is archaic, so it's time consuming to see what's already been entered.
It is a real bummer that the custom text triggering doesn't work better than it does. I do find that VI Pro makes good HP playback possible, and I've never used the VSL Finale matrices. I make my own (I mostly don't use the SE libraries anymore either), but it doesn require a lot of hands-on tweaking, some of which can be done relatively quickly on the fly. For instance, I usually have a layer of the matrix dedicated to the various performance repeat patches (legato, staccato, etc.). If I have 4 instruments playing a bunch of repeated notes, I can highlight all the notes, and with little more than a push of a button move their instruments to the appropriate level on the Y matrix. I find the repeated note patches make a huge difference in realistic playback.