@Gromit - I thought you'd never ask
Seriously though, I have had a very positive experience of using F mount glass on the Z series via the FTZ adaptor. In fact, I regularly use my Nikkor 70-300mm f4.5-5.6 AF-P via the FTZ adaptor and am pleased to report it works flawlessly. In fact, the small size and light weight of the 70-300 makes for a great combo with the Z7). Here's an image I took handheld with that combo:
Heroes by
Amar Sood, on Flickr
Nikon Z7 / Nikkor 70-300mm f4.5-5.6 AF-P.
This lens can be had for under £500 and is a serious bargain. (It's also weather sealed, unlike the 70-200/4).
Another F mount lens which I have adapted onto the Z7 is the Tamron 17-35 f2.8-4 DI OSD. Again, it works flawlessly and is capable of great results. Here's an image I took with it earlier this year:
Tryfan from Afon Lloer by
Amar Sood, on Flickr
Nikon Z7 / Tamron 17-35 f2.8-4 DI OSD
Again, this is another bargain and is available for under £500.
In terms of Macro, I also adapted the Nikkor 105mm f2.8 Macro successfully. Here's an image taken with that combo:
Marbled White (Male) by
Amar Sood, on Flickr
Nikon Z7 / Nikkor 105mm f2.8 Macro
Unfortunately, it's true that some older third party lenses won't work (unfortunately this includes your Tamron 24-70/2.8 SP G1). However, there are many lenses which work very well. In terms of Tamron lenses, here is an up-to-date list:
https://www.tamron.eu/service/compatibility-nikon-z-and-canon-eos-r/
This states the following Tamron lenses are compatible:
- SP 15-30mm F/2.8 Di VC USD G2 (Model A041): Serial number 004219 or higher or firmware 2.0 or higher
- SP 24-70mm F/2.8 Di VC USD G2 (Model A032): From serial number 040912 resp. firmware 2.0
- SP 70-200mm F/2.8 Di VC USD G2 (Model A025): Serial number 059178 or higher or firmware 2.0 or higher
- SP 150-600mm F/5-6.3 Di VC USD G2 (Model A022): From serial number 035591 or firmware 2.0
- 17-35mm F/2.8-4 Di OSD (Model A037): From serial number 006446 or firmware 2.0
- 18-400mm F/3.5-6.3 Di II VC HLD (Model B028): From serial number 052673 or firmware 2.0
- 35-150mm F/2.8-4 Di VC OSD (Model A043): All serial numbers compatible
- SP 35mm F/1.4 Di USD (Model F045): All serial numbers are compatible.
- SP 35mm F/1.8 Di VC USD (Model F012): Firmware 3.0 and higher
- 70-210mm F/4 Di VC USD (Model A034): Firmware 2.0 and higher
- SP 85mm F/1.8 Di VC USD (Model F016): Firmware 4.0 and higher
- 100-400mm F/4.5-6.3 Di VC USD (Model A035): Firmware 3.0 and higher
- SP 15-30mm F/2.8 Di VC USD (Model A012): update only via Tamron Service
- 10-24mm F/3.5-4.5 Di II VC HLD (Model B023): Firmware 2.0 and higher
- SP 45mm F/1.8 Di VC USD (Model F013): Firmware 2.0 and higher
- SP 90mm F/2.8 Di MACRO 1:1 VC USD (Model F004): update only via Tamron Service
- SP 150-600mm F/5-6.3 Di VC USD (Model A011): update only via Tamron Service MF only
*VC is not operational
That's quite a wide selection and I certainly wouldn't think twice about adapting via the FTZ.
Hope this helps and good luck!
Lefty