thanks all for the input.
my eldest currently has a basic Hornby select controller, but i was not aware how much further the technology had evolved over the intervening years.
To answer Nigel's specific points...
1) Yes, we would at least like some of the points to be powered (the ones on the far side of the board to avoid the 6yo crawling all over it to switch a point... As to whether they are DCC is a different point - I am familiar with the DC solution, and that would work really well too, and give the 11yo something to think about as we wire it all up...
2) smartphones... this is a sore point... Only the eldest has a smart phone, but its not that great. So, lets leave phones out for now (but maybe, future proofing...). My youngest (6yo) does prefer knobs to buttons.
Its looking like some more investigation on the Roco is in order :-)
