There's some good and bad here, the hardware is surprisingly good for a $250 open source laptop (cost + shipping + taxes) but it's nowhere near as polished or usable as a comparable $250 Chromebook. The software is squarely beta quality so expect to spend time tracking updates, flashing firmware and doing things like patching u-boot from someone's github repo, etc.
Daily use annoyances: the touchpad is mediocre, battery drain while the machine is asleep is higher than I expected. Lots of things that should be possible (ARM hibernation support) aren't because rockchip based their kernel on 4.4 and the mainline upstreaming effort is slow moving.
Desktop performance is solid though, as is streaming video playback. Basic system performance is great, storage is fast, system is responsive etc.
The Pinebook Pro specs compare to a somewhat powerful 6-core arm SBC: 5V power input, easy to charge off a solar panel on your boat, IPS LCD panel, MALI gpu, 4gb Ram (SoC is maxed out, this could be upgradable: Original $99 Pinebook upgrade kits are coming in Q1 2020), 64GB MMC, wifi, no ethernet (use $9 dongle, case too thin), USB-C, a UART accessible from the headphone jack with a $7 dongle breakout thingy, optional $7 M.2 NVME daughter board. This is a (almost) fully opensource chromebook with a magnesium shell, and hardware privacy switches. 2 blobs afiak for Mali GPU and Bluetooth/wifi module. Hackable. Inexpensive accessories already exist with good availability. Replacement parts available, BSD according to the wiki.
Personally, I like reasonably powered home computing devices, I just put the stuff with all the fans in the closet. Maybe doing a huge compilation or git merge on the Pinebook hardware is gonna be slow. Full video and smartphone graphics should be fine. Connecting your Pinebook to a Pine64 cluster for big jobs is something you can do today and sounds like a summer project.
This client hardware seems pretty decent for two large bills. A specced Librem 15 is $2000 and could be eye watering if it falls off your boat again.