Congrats. I've been hearing a lot about this lately so I'm hesitating on whether or not to get it but 6 months of wait time is crazy.
StanislasChauvin
I've had an Srpg27 for about 8 months and honestly it's been pretty accurate so far. The last time I've set the time was a bit over 2 weeks ago and I'm ahead by 2-3 minutes right now (+10s/day). This of course might be different to someone else's, especially considering that I had to re-regulate the watch a few months after I got it since it was running fast. For the price it's a really good movement that isn't scared to take a beating.
A GMT could be pretty cool. Seiko makes some but imo you should look at the Traska venturer, they restocked recently so are ready to ship. The sinn 556 and Seiko Alpinist (There's also a GMT version of the Alpinist which recently released) are also good options although I would personally get a unique colour to add some variation. Nice collection!
Gorgeous watch. This is a sinn triple date lunar calendar moon phase that was only available from 1990-1999 and is quite rare. This one seems to be in good shape and from what I've seen, they mostly tend to sell for over 2k.
The Miyota 9015 movement is considered to be reliable and the big range you see about the movement's accuracy indicates the most time you will possibly gain as well as the most you will lose. In reality you will probably get around+-7s/day which is quite good honestly, especially for the price.