Most dev on vita focus on improving performance on 3.60-3.65 and to add more function on those firmware. For 3.70+ the restriction by anti hacking make the tools and plugin not able to access a lot of setting/feature, which cause crash and a hell to try fix it, for example Adrenaline ,PKGJ ... so most dev do not touch those firmware.
You can downgrade your Vita to 3.60 or 3.65 and better do it now, since the tools for downgrade has been update to work up to 3.72, before Sony push some 3.73 and block it again.