Actually for good all-around performance, rims should be about 80-85% of the cross-sectional width of the tire, or else the sidewall will be excessively stretched. Remember that the 185mm (or 7.3") refers to the nominal width of the sidewall where it bulges the most, not the tread (which is narrower) nor the bead of the tire (the edge that mounts to the wheel) -- that sidewall needs a certain amount of curvature.

For the 185 tires, Volvo designed its 14" wheels to be 5.5" (20mm offset), so 5.5/7.28 is about 76% because it isn't considered a performance configuration -- as I wrote above, for performance you want a slightly wider wheel, but not one that is as wide as the nominal cross-sectional width at the middle of the sidewall.

Volvo's Turbo setup, in contrast, had 15x6 wheels (also 20mm offset) on 195/60-15 tires, so you had 6/7.7, which is around 78%, still not great. On my own car, I have 205/55-16 on 16x6.5 (25mm offset) Hydra wheels, so that's 6.5/8.1, or 80%, a little better.

re: "...should i get 22mm or 25 in front and 30 in back? or 22 in front and 25 in back?..."

Where were you planning to get the proper lug sized wheels (i.e., 5x108) in those weird offsets you mentioned. It's hard enough to find any wheels for these cars that aren't Volvo-made, let alone getting them in those strange 22 and 30 mm offsets. The 240's standard size is 20mm, and the 700/900's size is 25mm; and that's about it, unless you go to very old wheels (140/160 era) or FWD/AWD current cars's wheels with larger offsets.