Apparently I can not edit this post further which is a little dampening as I just regained the drive to continue, though I dunno if anyone cares about spells past the Third Level since they are very unreachable as of the EA.
You could make new updated thread as required. I wouldn't worry about going beyond spell levels 3 or 4. As majority of the game should only have 3 or 4th level spells as the most.
If we did make a 3rd and 4th level list, I would make sure we highlight the highest priority spells for character build diversity. They will not add every single spell or subclass so we must point out the item spells and subclasses. The other stuff should get added it at some point but our goal is the best launch game possible.
I am really routing for booming blade and Green Flame Blade make it. Those two cantrips are very important for many classes/subclasses. Slow, Haste, Fireball, Hypnotic Pattern, dispel magic, counterspell are a few key third level spells. Though with how reactions work in BG3, counterspell will be strange. Same as the shield spell.