With Autodesk each year making it more difficult to write add-on software for AutoCAD LT, one developer tells me his solution:
...[we] are in the process of porting our apps to Bricscad Pro.
Makes sense. Bricscad Pro (1) is half the price of LT, and (2) has most of the APIs of AutoCAD.
The primary drawbacks are that LT has these allures: (1) it is an uncrowded market, and (2) its size is 4 million -- something like 10-25x larger than that of Bricscad, I'm guessing.
So, it's hard to say from which market the developer would make a larger income.
Win, win, draw.