Dr. D-Flo has an interesting large format 3d Printer project that he's putting together:
It has lots of interesting and innovative features that could (and should) be incorporated into smaller builds.
The $5000.00 pellet extruder he's using alone puts this out of reach for most folks, but I don't see why it couldn't be put together with a standard extruder using a .6 mm nozzle and some 3 Kg spools of 1.75mm filament.
His use of the Duet 3 controller board, controlling heat cut out sensors is very clever, and could be used on any FDM printer for increased safety.