I'll definitely try the Voyager brake control prior to changing - sounds like it may do the job just fine. Still need a trailer, so talk of upgrading is premature!
As for the conversion, it was in rough shape so I opted for the *newer* Astro- the v6 4.3 of the Astro is plenty, and allows my better half to use it for short distances without gassing up like crazy- as would be the case with a v8 5.7. I plan on adding an extra
battery for use at the campsite (hooked up to the main
battery with a relay in between), blinds for the tinted
windows and an emergency crash mattress :zz
thanks again for your feedback - very helpful to a newbie like myself