Another tool to consider is producing multiple dithered negatives, and possibly masking out sections completely, so you can build up various parts of the print slowly in several passes. Keying your frames becomes a bit of an issue, and it is also a larger hassle to deal with than being able to produce a working negative from a single print run, but it can allow a little more control and apparent resolution out of your gear.
You can do a lot of rather neat things when playing with dithered negatives in multiple layers/passes, such as generating some specifically to be vibrated a bit over the print rather than pressed into a firm sharp contact, while others can be handled in a more traditional manner. You also have the option of retouching the negative manually by hand in a few specific spots with less risk of 'ruining' the whole thing if you're doing a lot of retouching. By retouching the negatives in effective layers you gain a safety net because if you do happen to screw up on one then you can rerun a new copy of just that layer without affecting areas that were handled on other sheets.
It isn't the easiest method I've seen used, but it does offer some rather neat options.
