A couple of things so i can return to the game after stop playing when 2nd edition released:
-Dounle turn gone! Double turn is an interesting mechanic that doesn't work with most of the armies or requires strict list builidng. In order for the double turn to work armies must be designed around that rule and have viable unit choices that help defend against it. Thats not the case and it won't ever be so there will be cringe games forever. Also is so anti-player waiting for your opponent to play 2 consecutive turns doing almost nothing. It kills the fun and nobody will miss it, instead many players would come back into the hobby.
-Free summnoning gone! When 2nd released they said that free summoning was implemented as an overall point increase in each army using it. Again this is not the case and ended be such a ridiculous experience. I guess they wanted to sell more models...
-Design armies and miniatures with rules in mind and not the other way around, so all armies are well balanced and have plenty of choices. This info i got from an interview i have watched and if i remember correctly (correct me if i am wrong) they mentioned that first they deisgn the miniatures and then they try writing the rules for them.
-Battalions gone! Poor choice of battalions for most armies intestifies unbalance and adds to the double turn problem. Let players roll for 1st turn maybe with a bonus for the player finishing deploy first. Also battalions lock you on what kind of units you can field. I guess here is another marketing choice with certain battalions forcing you to field a couple of uninteresting weak units that wouldn't sell otherwise...
-Battletomes gone! Welcome to the modern age. Free rules online that can be updated on the fly. Also instead of point adjustments start fixing some useless or problematic warscrolls (you did it we KO and thunderers). Points don't solve useless rules becauses they can be reduced or increased up to a point. Free rules help new (and existing) players see can an army can do before buying. Keep books for lore, narrative and campaigns.