Lee Carré (2021-07-25 11:24:55+00:00): I'm very local. Lots of GNSS tracks are on my to-do (‘wish’?) list along with other types like Mapillary images (once I have the equipment). Some roads have zero. Those that do tend to be major roads (and common driving routes) with only a few separate (in time, or user / device) traces. I, too, have noticed (and been irritated by) the several-metre misalignment of various imagery (with no (nearby) offsets stored in the public DB); seemingly differing by imagery supplier. It's particularly troublesome for small elements.

I did look into applying & uploading offsets based on GNSS (when mapping a small path, for which the alignment was clearly several-metres off in a systemic way), but the GNSS receiver in my nano-computer doesn't seem accurate enough to do so reliably (at best, regardless of software-reported accuracy, it seems to be ~5m). I'm hoping to visit the handful of known survey-points, and find any others (e.g. asking the Planning & Infrastructure departments), as a starting point to get a quantitative handle on the uncertainties involved.
A better external GNSS receiver might be sensible, too.

Since I'm a relative newbie, what would you recommend as strategy?
Major roads by car first, then minor ones, then footpaths?
Broad-strokes across the island, then detail in dense areas, or complete one area before starting another?
I don't really do arm-chair mapping, so I'm unsure what would be most helpful for those who do, or for imagery-alignment.

So far, I've only captured some small tracks of missing features (e.g. the odd footpath while surveying). Though, your mentioning of tracks has reminded me to name+tag+describe+upload my remaining ones. I've not yet done any large captures, though it seems (technically) straightforward & uncomplicated.

Unfortunately, there's only a handful of locals contributing (and it's even worse for the other islands). Not even enough to use the term ‘community’. Yet, self-evidently, a lot of work still to be done.
Thus, I'm thankful for changesets like this, which help a lot.

Ideally, some better (resolution & recent) (& libre) imagery would be good. Small islands are often neglected (memories of fuzzy & very outdated imagery from Google, when they were the only notable source). The catch being that very few locals have even heard of OSM (there isn't really any tech-culture here), and I've only seen a couple of drone pilots (but never managed to speak with them about the possibility) who have UAVs capable of decent altitude while carrying a camera. Chartering an aerial survey by traditional airplane (e.g. a private-pilot Cessna) would be expensive (landing fees, here, are considerable). A balloon would be tricky, due to never being far from the airport.
The States did, some years ago, commission a survey by military helicopter, for purposes of checking compliance with Planning rules, but haven't released that data (and even when they do release cartographic data it tends to be with a proprietary (OS-style, or simply ‘all rights reserved’) license, even for matters of public-interest); I've been meaning to talk to them about that, too. However, someone with your standing might be more persuasive (unless experience shows that it's better coming from a local)?

Any other suggestions or advice would be appreciated. Feel free to PM me (since this is already off-topic for a changeset discussion). So far, most of the input I've received has been from those who are far away (notably Germany), and when these islands have enough non-trivial differences from the mainland, the culture-barrier becomes a factor, particularly when it comes to how to map something unusual.