Hey Steve, I haven't been around here much lately, but I always enjoy reading your threads. Sorry to hear about your gsa/gda battles. Here's my experience with gda, experience only, since I offer no answers. I have 3 tanks - 2 - 50's and a 10. All are pressurized, dosed via modified EI.
The AGA 50 is lit via a 96W AHS kit plus a 30W std strip. Rarely gets any gda, though I wipe the glass weekly with my water changes, I could easily go 2-3 weeks without needing to wipe down. This tank's photoperiod is 1.5 hours longer than the others (9.5 hours vs 8)
The Oceanic 50 is lit via 2 - 55W AHS lights/reflectors. This tank is on a back wall which faces 2 windows which face east - meaning in the mornings, you could argue it gets hit with a fair amount of 'brightness' though not necessarily sunlight. This tank needs weekly wiping for gda or in 3 weeks it will look like your pic does.
The 10 is lit via 36W ahs kit. It lies somewhere in between the 2 50's in gda levels and wiping requirements.
I have tried leaving gda alone for 2 months, then wiping, vaccumming, and found no difference other than streaks on the glass from snails which do slowly eat the gda. Filter maintenance (Renas on the 50's and HOB on the 10) doesn't have any effect on amount of gsa. The only thing which I believe (no scientific proof here) improved the situation some was cutting down on the photoperiod and my micro dosing. For a while, I was adding micros daily and noticed that I was having more gda than ever before, including getting some on Anubias leaves. When I cut this down, it improved it some. I suppose I could really try to narrow this down and get more specific needs, but I just don't have the time nor the inclination to get very scientific and get the 'perfect' balance. After all, it's a hobby, which is supposed to relax me and provide enjoyment, right?
Anyways, sorry for the ramblings, but just thought I'd throw a small tidbit at you there.
BTW, tank and fish are gorgeous, even with the gsa!
No, it never does get boring - thankfully!