Hi,
Worth reading on, but you won't like the first bit.
Microlight hours count for very little, and for a CPL count for nothing!
(basically, if you have a microlight licence you can get some hours off an initial PPL/NPPL, and if you want to be a microlight instructor you'll need some microlight hours, but that is that)
The maximum permitted take-off weight for a microlight is 450kgs, but many microlights have a lower maximum weight than that - for instance my Quantum has a max weight of 409kgs.
Now, there is no minimum weight for a light aircraft - it just has to be registered as such.
So a Tipsy Nipper is a light aircraft, but weighs well less than most microlights.
Even stranger are things like the Kitfox.
A Mark 2 can be either a microlight or a light aircraft, for instance. Some of the microlight ones were built as and registered as light aircraft, but got reregistered as microlights when the tough JAR medicals came in. Some of them then got re-re-registered as light aircraft when the lighter NPPL medicals came in!
So, you could buy a microlight - but only certain ones - and re-register it as a light aircraft. But if you don't re-register it, then the hours won't count for your CPL!
No-one actually does this, however, since the microlight versions tend to sell at a premium to the light aircraft ones for some reason.
Have a look through the PFA (LAA) magazine and you'll find a world of kit-built light aircraft that will do the job for you, and pop in to Strathaven to have a cup of tea!
Very best,
XA