Sounds Like your on track in looking after your bank. Desulphation is a sloooow process,    Also does your  Studer charger have a batt temp sensor option if so this will be an essential item as well I know the larger studer inverter charger units have a BTS . There not expensive and are a simple plug fit . If your solar charge controller also has a BTS option,  I suspect from your description of a 30 day auto equalise cycle  it maybe a Xantrex C60 CC then fit one to this as well then both units are singing from the same hymn sheet.