Ok, some comments, I had to register to give them :-)
If you are doing an Ausf. D you don't really need to provide both MG34 and MG42's, buy the time the Ausf D was introduced all infantry used the MG42, MG34 was ONLY used on tanks and in armoured cars. Save yourself some space on the sprue, I'd rather have ammo boxes/belts/drums for the MG's than extra MG's.
Also, I think -- sorry if someone already have said this -- a useful combo kit would be something like providing /1 /7 and /10 in the same kit.
Basic halftrack, add 37mm to get the /10 command vehicle, replace with 28mm squeeze bore (not on all so is not essential if you can't fit it on the sprue) and add field bridges to get engineering vehicle. I think the /7 had some different internal layout to accomodate the assault engineers' heavy equipment but I don't think it's necessary.
Providing opening doors would be very useful!