Halo 4 forge is good, but I scratch my head as to way they took out the fine-tune tool. This is a basic necessity for serious forgers and must be returned. In no way do the magnets replace this tool. I used it with almost every object in Reach.
Nothing compares to the lack of this important feature. Add it back, this shouldn't be too much to ask.
Also, lower object limits, and a large, empty, flat terrain map to forge on.