Looks like keeping it simple and flying PIC ourselves the normal way is hassle free. It is not worth to be audited in a grey area which is up to the individual inspector's interpretation of regs.
There is no grey area to be interpreted. In the USA both handling pilot and safety pilot of a single pilot aircraft
can claim PIC. In EASA land they
cannot. That does not stop you from flying it and logging it. You just have to understand that you cannot go back to Europe and credit the SP hours towards requirements for Part FCL licences.
On the other hand, if you were to end up pursuing an FAA licence (bearing in mind the growing shortage of pilots out there) those hours will count toward your total. If you are going out there to hours build with a buddy I can't see any good reason not to log a few free PIC hrs and have them in the nudge-bank. You can record it on a separate sheet (acceptable in the USA) if you wish so as not to confuse those concerned with the provenance of EASA logbook entries.