What I can remember, beyond the truncate-before-transcribing issue that made labels too long was 'Gat' -> 'Gata' changes (with Ægisgata, I got bogged down in the Ægis and ignored the four-letter 'Gata' shouldn't be truncated to 'Gat').
What I can confirm from my travels around Iceland is that there are, seemingly, no official abbreviations. The entire name is always spelled out on street signs (e.g. "Ægisgata"). So, I used the first three letters as abbreviations for all Icelandic street name suffixes.
While one could certainly opine in favor of doing something different, this is a purely stylistic matter and one for which a decision on how to handle Iceland needn't impact any other country. I would therefore not think it worthwhile to go through every file and replace every instance of "Gat" with "Gata", "Myr" with "Myri", etc. unless for some reason it's
really really necessary.
Also, thanks for the datacheck link. I had heard legends of the mystical datacheck page but never seen it prior to today. I've already fixed (or should have fixed - let's see!) all of the red errors and flagged some of the black ones as false positives.
How fussy do we want to be about the visible distance errors? I know there's a guideline that points should not be more than 10 miles apart, but a lot of Iceland is rather sparse and oftentimes there simply are not any intersections or points of any particular interest for longer than that. As it is I'm pretty sure I've co-opted a few people's private driveways to make waypoints out of.