Fiddling with it at the moment. I don't believe it would be a major undertaking as at least one scenario has the entire defending OB HIP at start anyway. The biggest balance issue I see at present is multi-level buildings as these add quite a bit of options for the Scenario Defender, especially so since they tend to be stone structures. Initial impressions of adding concealment seem to be somewhat offset by the addition of having vehicle crews (crew survival). One thought (not tried yet) was to add halftracks to the entering side's OB, though I have to check historical availability and ultimate influence of increased mobility. Pretty sure someone , probably someone much smarter than I, will come up with a viable adaptation.
There are/were a couple threads on Elst in full ASL. I'd play the multi-level buildings as single story, but I've done it both ways. Concealment, I found, wasn't much of a problem because there are so few Germans that they tend to have to shoot early and often rather than skulk and wait for PBF. Frankly they could probably use the extra help staying unbroken as well.
If I were to suggest any changes, it would be to start CG scenario 1 with all Germans HIP or at a minimum give them a ton of ? counters. The opening scenario of the CG has so much potential for recon in force but instead the British player is either driving right up to German positions or managing his encirclement from the first MPh.
Also be prepared to deal with Fire in the RePh as you see fit.
I enjoyed both of my full ASL ruleset playings, but I think the Germans could use a bit of help balance-wise.