Quick conveyor build defaults to the selected transport level

I get muddled with laying the wrong conveyor levels all the time.
When selecting a conveyor end, to build, it would be great if the build chose the same level conveyor as the existing one. Ie. Mk1, mk2, mk3

Also, I think the current transport level should be settable and shown on the screen somewhere. Any time I place a transport, it should start at this level.