If you mean bigger geographically, maybe, if the number of MLAs in the district is smaller. That's true in the North.

It's clearer to say that, the fewer MLAs per region, the less proportional the result. Three-seaters are to be avoided whenever possible, because governments love them: in a place with two main parties the strongest party will usually win two of the three seats, creating a "largest party bonus" which, if there are too many seats like that, will give that party a "manufactured majority." Eamon De Valera perfected that trick in Ireland. After his retirement they rolled back the number of three-seaters, but they still have far too many for my taste. The current BC-STV map has only three, all unavoidable.

You mght think the Green Party could never win a seat in a four-seater, but you'd be wrong: in their strongest district, if they are lucky, if they get 14% or more on the first count, the second NDP or Liberal might drop before the Green candidate does, and give the Green enough transfers to get elected. Still, in general the Greens want six-seaters or seven-seaters.

The same principle applies to regional MMP with self-contained regions, as in Scotland. They have no legal threshold, but with 16 MPs to a region, and using "highest average" rather than "highest remainder" for their rounding rule, in practice a party needs between 5% and 6% in the region to get a seat.