32/62/90 performs fairly similarly to 32/64/90, it's maybe a couple of percent slower but hard to tell for sure. There is a slight reduction in relations needed, but the lower yield means more sieving has to be done at higher Q values where the sieving is slower. There isn't any noticeable improvement in matrix size.
In hindsight, I shouldn't have been expecting the algebraic side to behave too similarly to the rational side: the larger norms mean that more of the relations have two large primes close to the bound on the algebraic side than on the rational side.
I could try 32/63/90, but it's hard to imagine it'll be more than a percent or two faster than 32/64/90, so I'll just stick with the defaults from now on.
