A very useful option for FT2 users would be add this option into misc menu:
Choose Back key Delete mode: (Renoise/FT2)
In Fasttracker2 (Backspace key delete current row and upper rows if pressed).
Renoise do it in a ST3/IT style (delete selected row and lower rows if pressed)
Im sure this option would make FT2 users more confortable into Renoise.