well at 7% a player would be waiting 9 turns before the mines are probably set up. Mines are very plentiful. The drawback would be the unspotted mines that your own traveling units might trigger. I mean pillbox as a static defensive position set so that its reduced value (when vacated) is just above BUNKER. Would flavor the front and strongpoints. I've also toyed with the idea of making bunker/pillboxes as immobile units with facing. That way as vehicles they would be more accurately represented. Not lending to the defensive values of other units besides the entrenching that would be within their hex.
Just suggesting lowering the zoc movement multiplier to get a taste of greater manuevers across enemy flanks. So that armor can move between a gap of two units into their flanks and still be able to fire would seem realistic. Also, fixed units on map are unrealistic. I personally like no limited air recon, as that is the main purpose of air recon (to direct artillery/airstrikes). If the units aren't under the players control waiting in the rear I think they should be used as reinforcements. If they must be on map as fixed (such as defensive unreleased) formations; they should be in defensible terrain with AAA cover, and not in road column. Although, I think that would be unrealistic as they're in theater and yet the commander cannot issue orders.