To describe the Nesscraft (first one I have ever seen or heard of). as a sportsboat or to contemplate the changes you mention would be;
as they said in THE CASTLE; (he's dreaming).
You are on the right track with a Young 780 if you want to race a boat. As with any boat, either get a surveyor or have a really good idea of what you are looking at, beauty of smaller sports boats is a lack of "systems" that need checking, just verify hull/ rig integrity and sails, an outboard and maybe 1 or 2 thru hull fittings, anymore than that, (head and sink) and you are not looking at a trailable sportboat, the quick ones will not have any thru hull fittings.
I would look at the websites for Trailer Sailors or go to ABSA, (sports boat assoc.) but the boats listed there are very preformance orientated.
Good luck in your search, the 2 links below will show just how different your search can be.
A.S.B.A. link,
asba.org.au/Trailable Yachts assoc.
www.tya.yachting.org.au/
, I got myself a nice Farr 740 it is competitive and still has some accomodation. Decided for the Farr against the Ross 780, the Farr will allow overnight stay at Rotto in some comfort and has better resale value also it is plastic against western cedar and epoxy. First race will be next Sat, looking forward to it!
. Found that the electronic is a bit dodgy............ but that is next weekend work a few dry connections, also 1/2 way in the race had to pull off as the main halier snapped at the shackle and lost the rope in the mast 
, reroping is my next project! 
I will post some pics! you can see her here!
Wish I could do that with my wife!
