Wow that’s a long collection.
We fly with 4x battery sets and the charging case with a little generator for our M300. So far, we have only gotten 5x hot swaps (6 flights total) with that setup (~1.5hr in DJI Pilot). Then we take an hour break to transfer data, eat something and let the batteries/charger catch up… then do it all over again. So far we have been able to do this 3x per day (nice long summer days).
Base station can stay where it is unless you have security concerns and want it close by. In general you are clear to roughly a 10km radius, out beyond which you may start to see 2-3cm of separation. Although, watch your battery drain on the RS2 or what ever base you’re using… we usually hook up a simple USB battery bank to it to provide that all day power security.
Overlap: DJI Pilot is so wasteful on the edges you’ll have no problem with enough overlap. That said, you shouldn’t really need much of any overlap to merge anyway given that both data sets are calibrated. ie running strip alignment on the R2A isn’t particularly useful given its internal accuracy, hence overlap only serves to verify accuracy not augment it. Though you could use the global shifting in RockCloud if you see a simple issue.
GCP distribution: if you want an orthomoasic, that will govern the GCP distribution. But you’d be in 2D ortho mode so not nearly as stringent as say a normal photogrametric flight. We default to 3-5x per flight group (how many hot swaps we can do), and just spread them around to each unique part. That’s gonna be tough in your area.
As for the DSM in DJI Pilot, we are testing our first run of it tomorrow. It is a bit of a learning curve though. So be careful.
Best of luck
Please share any lessons learned on the DSM part.