Knights & Knaves and the AD&D community are not places I'm welcome, but I am happy to hear OSRIC is getting a new edition. Personally and I know the AD&D gang wants to hear nothing I have to say I think it could benefit from two different approaches that might be hard to reconcile.
1st - Simply streamlining and cleaning up the 1980's language and layout issues of AD&D and moving the disparate parts together from the various books ... even when they don't make sense. Example: bring the various lb and coin weight approaches to encumbrance together - the specific encumbrance by item and the generalized system right next to each other. Let the reader figure out how to use it best for their table, but present it all side by side. Let's call this the "OSE" format
2nd - Really build on the work of AD&D auteurs like Anthony Huso/Blue Bard and make a "best practices AD&D" from Gygax's creative slurry. Call this the "Errant" version.
Bonus Option ... guaranteed to provoke spitting and hissing among AD&D obsessives. Fix the system however, but spend the time lavishing love and creativity on what really makes AD&D special ... all the implied setting. The items, the random encounters, the spells and monsters. Just twist everything a bit. Put it into a slightly new setting. Not much, but maybe a bit more Dunsany or a stronger doom and darkness vibe. Heck go with the apparent AD&D end game (it's not domains) and make it a world of cosmic struggle where adventure consists of fighting against otherworldly incursion, and ultimately incurring into those other planes in revenge.
Anyways - glad to hear the project is going forward, and hope it can make something interesting in the end. The original OSRIC managed a solid retroclone, so something else is needed I think.