I'm farely new to moi3d but getting my feet wet and dirty finally. I've been a Maya nurbs modeler since the alias days so I'm constantly amazed how well moi nurbs work right out of the box.

Couple of suggestions:

Export mesh. It would be great to select isoparms of a nurbs surface and have the mesher algorythm know that it needs to respect those isparms as poly edges. This is handy so that you can further work areas in another 3D app but not run into the situation where the edges aren't orthographic as in a sphere where the polyedges along the equator arean't exactly in half of the sphere.

Also along the idea of setup for meshing would be the ability to save to an file user settings. This would be great to make adjustments on simple geometry and then recall on larger files that need to export.

Maybe a way to paint or setup a tolerance for trim edges to more align to non trimmed surface edges when going to a polygon. I realize it's doing this by welding vertices but if there was a way to adjust paramiterazation of the trim surfaces to look at adjoining non tri surfaces and try to mimic there topology. That would be really really neat.

Rebuilding surfaces and attaching in programs like Maya works awesome. Be great to have some of that functionality but I realize moi3d keeps things simple and I love that about it and is probably why it takes so much time to make great nurbs geometry in Maya as nurbs are very complex beasts.

My only thing I find difficult in moi3d at the moment is that if I want to select for instance edges and I have already drilled into the edges and select to drag a non crossing window around more edges, moi will instead grab the object if it's faces are below my cursor and then instead I grab the object and move it unexpectidly.
Not sure if I'm using moi properly but a menu system to maybe disallow selecting faces or edges or points (cv's) ala Maya style in the GUI would be helpful.

Love moi, it's my not so secrete weapon at work these days!