If you're worried about thickness you're not going to do a lot better than rigid foam unless you get into some really exotic material. XPS is about R 4.5/inch, polyiso will get you up to 6.5/inch for double the money.

What about using the Polyiso between the studs?

Fiberglass or cellulose is always problematic in a basement due to the possibility of moisture, which will severely compromise the R value and provide a home for mold to grow.

In your situation I'd put 4" of the rigid foam against the wall then a stud wall with the 2x4's sideways (eg 1-1/2" thick) against it to attach the blueboard and provide a cavity for wiring. Plus spray foam in the perimeter joist bays--they are too hard to fit insulation into correctly by other means (and it's fun to do!).

I am in a warmer climate (Virginia) and I used 1" thick rigid foam on the walls for insulation and vapor barrier, and then framed 2"x4" walls inside, with rock wool batt insulation and drywall. I also cut rigid foam for the rim joist area and then spray foamed around it to seal it in place and added the rock wool. I used treated lumber for the sole plate, and also put thin foam insulation under it for vapor barrier and to seal it to the floor. I used a power nailer to attach the sole plate to the floor.

I also had them install the drywall with about 1/4"+ gap off the cement floor, and they installed the baseboards with a slightly smaller gap. My intention was to prevent any direct contact between the cement floor and the framed wall surface, since its an old house and there is no vapor barrier under the concrete floor.

Low expansion spray foam for windows and doors is a lot easier to manage than the standard Great Stuff foam that seems to expand way too much. Also make sure you wear disposable gloves, since its nearly impossible to get dried foam off your hands.

Bruce