If there is a better board to put wishes on I haven't seen it. I also posted this on AUGI's wish list today.
I wish the trim/extend command would give you a fillet option in the options bar. when checked you would enter the radius or if blank the radius could be manually drawn like the current fillet does.
This would save a lot of time creating fillets. The current method of drawing a line, selecting fillet arc, selecting 2 lines, fixing the radius is very click intensive. By allowing the command to be a part of trim/extend, you could simply set your radius and fillet a ton of lines very quickly.
The other advantage is that for autocad users learning revit, this method is very similar in process to the autocad fillet command and dovetails nicely with the trim/extend command's method of picking objects on the side you want to keep.
I can see how setting the arc radius ahead of time would reduce the clicks. When I tested this (using the current fillet arc option), it looks like there would be three less clicks per arc if the radius could be specified ahead of time.
The following link is setup for you to submit feature requests directly to our development group:
Even though there is not a fillet option included in the Trim/Extend corner tool, there is a "radius" tool that can be activated before starting to draw a chain of lines or walls.
However, I agree; it would be nice to have a "radius" option for the Trim/Extend corner tool.