When I looked into it, hourly costs on a shiny new c42 weren't much less than on an old group-A aircraft like a C152 or PA38. You can do a NPPL on group-A aircraft with a group-A instructor then upgrade your license, but microlight hours can't be made to count towards a PPL or CPL in the same way. In your position I'd do an NPPL on group A aircraft and retain the flexibility to add ratings/upgrade my license at a later date.
e.g. an hour on a PA38 at inverness is 158, but an hour on a c42 is 150. Admittedly it's 110 for the microlight at Glasgow...