I’m with the group not seeing a contradiction between modern and boxed sets. The Avatar Starter Set at Target is absolutely a modern boxed set. Do something like that. Nerd Immersion did a review today that goes through the contents.
Looking at 4E and most OSR games for more useable and modern layout and design would be a huge step up from the current WotC standard. Using double page spreads. Mini maps next to room descriptions. Keep everything compact and readable instead of sprawling and tucked away.
Likewise, you don’t need a column for a monster stat block, for example. Not even 1/2 or 1/4 of a column. Look at Goodman Games’ Dungeon Denizens. The 5E version is 100+ pages longer than the DCC version because the 5E stat blocks are ridiculously oversized. Same monsters, same text, same everything…except the stat blocks.