That's because most people don't qualify for ECO. I have yet to see a "normal" house & customer who qualifies for ECO. I talk with lots of Green Deal Assessors and work on a countywide Green Deal group and none of us have found funding for "normal" customers yet. I've heard from several sources that there's still some funding via CERT available for cavity & loft but it's got to be installed by the end of March so you'd need to get your skates on. It's not easy to find - I'd suggest you look for a list of insulation installers in your area and ring each of them to see if they have any funds left.
ECO is still a long way from being resolved I know of one installer who generated 1200 jobs for ECO, a substantial amount of them were solid wall jobs in a low income area, the utility who had requested the work couldn't work with the jobs provided because even in a low income area they weren't skint enough to make ECO worthwhile for the utility, the goal posts had moved within a fortnight of requesting the work from the installer. ECO is going to deal with social housing primarily, easy target - lots of houses one load of permission from one landlord and economies of scale.
My understanding of underfloor heating was that it was more efficient as it takes a hot water feed of 35 degrees. However, I've recently been on air source heat pump training and the software used for MCS certification shows absolutely no difference between underfloor and radiators. I've queried the figures but it looks as though you wouldn't gain from ufh even if you were prepared to retrofit.
