There has been a lot of research on how, depending on habitat, deer can move seasonally spending more time in one part of their home range during one part of the year verses another. On larger properties where you can reduce the home range of a deer and keep a large part of their time on your land, spring plots make sense to me. Also if you are in the south and trying to cover the summer stress period, again with a large enough parcel to operate on scale. We all have time and resource constraints. I think that one small properties, a couple hundred acres or less, resources can be better applied focusing on the season. This excludes cooperatives and other situations where you may not own sufficient land, but you have sufficient influence on adjoining land to consider it part of your management plan.
We've got around 400 ac with about that much in adjoining land with some level of influence. I'm still planting warm season annuals to cover the summer stress period here in zone 7a and trying to do QDM, but we are probably on the ratty edge. I do think there are some deer that spend a large portion of their time on our land because of the year round plots. Also, we were in a unique situation similar to the OP in that we had no ag but pasture within 3 miles. Our biologist told us one of the reasons we had such a hard time getting our numbers under control was that during the summer when native food dried up, our soybeans were the best food in town. Deer range further when quality food is scarce and for every hole we left in the social structure by killing a doe in the fall, one of the immigrating does would stay and take its place. Eventually a combination of disease, coyotes, and our hunting pressure got numbers under control.
The OP was looking to spend more time creating new plots. That to me meant resource limited at least in time. So, from a priority basis, I'd place most spring planting as a lower priority in the north especially if the property is smaller. The exception of course are crops like beans and corn that are planted in the spring but last into the winter stress period. Perhaps folks up north have less weed issues, but I find much more success with planting most perennials in his plan in the fall.
Thanks,
jack