there are folks here who can give really good answers... given some time...
you might SEARCH on all the trailer postings - both here and at
http://bbs.trailersailor.com/forums/macgregor/index.cgi
http://macgregor.sailboatowners.com/
there some basic things.. check you trailer wheels to have no "play on them". If they have bearing buddies - then make sure they are greased.. do you need a spare tire?
I am paranoid - I bought some reflective tape at WalMart and put strips on both sides of the trailer and on the BACK of my boat.. I have not seen else anyone do this.. Seems extravagant - but then one time my trailer lights failed (broken wire)...
I firmly believe that driving here through Dallas.. that people don't expect to see a big sail boat going over an interchange - 100' over the ground - at 60 mph.. So I put reflective tape on both sides of the aft.. Mine reflective strips are are sticky (3M type) - (I have a D - so I have to be frugal...) - perhaps you could add some extra LED lights - along the rail - for improved visibility..
Somehow at night, those blue boats might blend in to the the darkness.. So even if they go faster, they still need more lighting aft...
check trailer wiring.. talk to more Mac owners - send some folks some emails..
TIE DOWNs... I WOULD NOT go down the road without more tiedowns on my boat.. it is just too light up front...
I tie the boat down...
1- Bow Eye to the trailer below using a webbed strap (pull tight - about 1000# break strenght..
2 - TWO wide web straps that go completley around the boat - one at the MAST and one at the END of the trailer...
3 - (probably overkill....) I tie a third wide strap from the rear Web Strap (at the cockpit hatch) with a strap to the aft of the boat, run it down, and then connect the trailer at it's rearmost location...
My boat is thoroughly tied and strapped to the trailer...
Paranoia is a good way to go...
I plan on putting trailer "tie down eyes" on the trailer this spring - to make it faster to get on and off the water...
--jerry