Is there any explanation of SparkPNT/Facet/Torch/etc. product purposes/versions?

Sure - I’m assuming you’d like an all in-one device? The new models here SparkPNT Facet FP - SparkFun Electronics all have -T version (scroll way down to see 6 models, 3 are -T “tilt” models). These represent our most capable RTK devices to date! Scroll a bit higher up to see this rough quick-comparison

All of these will work as either a base or rover (basically any of our products with RTK or PNT in the title can be base or rover, except the DA10N from your link).

We also carry versions of all of these varying combinations of included batteries, form factors, screens, etc (or, some without any!), but very few have tilt compensation. Here are the others
Torch (waterproof, fun form factor)
X5 + IM19 breakout

We carry more but they are out-of-stock right now, so I’ll save making this more complex for now.

Let me know if you want links for the more DIY (less plug-and-play) devices!