Hi Paul,
Assuming classic main and not furling as the 33.7 is the first series.
There's a couple of things regarding mainsail hoist.
1. There is 'max' hoist which is how far you can pull up the halyard until it two-blocks at the top and can go no further.
2. And there is the "P" measurement which is normally defined by a black band on the mast...which will be anywhere from 4-15" below the 'max' hoist.
The "P" will be listed on your rig in your case 34.6'.
The black band height or 'p' is what a sail can legally be built to for most rules and in the case of many cruising sails, the mainsail will be built short of that to allow for stretch and for tensioning the luff with the halyard. In the case of a racing sail, the luff will be built to the black band length and the luff tensioned with a cunningham.
Normally, you don't want to get to close to the max length on mains as you need room to accommodate a headboard without hitting the backstay..so even on a boat without a 'band' you would build the sail shy of the max distance.
Regarding the loose foot: Yes, perfectly normal.
Hope this helps.
Bob Pattison
Yes, the luff is tight and all the sail is hoisted. The downhaul is loose.