I don't know how that map and other similar maps I've seen squares with canon but it's interesting to see the Federation as the biggest bloc and divided into two "islands" with all the logistical problems and strategic perils that follows on from that. Where the Klingons and Romulans are placed, it must be a tough business trying to defend that.
That's the old
Star Charts book, its map design perpetuated in the newer
Stellar Cartography and even STO. It's not just two islands, it's all sorts of pseudopods and blobs and distant annexes and other stuff no conquest- or defense-minded star empire would ever put up with. That's basically the only way to make the UFP both 8,000 ly wide as required, and compact enough for certain storylines.
Romulans and Klingons both kinda straddle or at least kiss the A/B line there, for storytelling convenience. Neither placement is canonically set in stone, but there are some onscreen maps that place the respective national symbols or related star names in those rough locations. Romulans are kinda small - they are nasty customers, but supposedly they are kept behind the RNZ which was established way back, when they cannot have been particularly big or they wouldn't have lost the war to the puny Earthlings. So they don't really cut the UFP in two halves; their compact ovoid space just floats in the middle of the "right arm" of the UFP.
Klingons have more in the way of conquered space around them, but more strategically compact than with the UFP. Cardassians are a second-rate power. Etc. Lots of guesswork, some outdated tidbits, and it doesn't really prove anything, but it rides on a certain assumption about the relative and absolute sizes and tries to make that consistent with onscreen facts.
One really wonders if the Ferengi hold any territory at all, outside their home system. I mean, private Ferengi probably own planets everywhere, or otherwise have them in their back pockets, but the Alliance is unlikely to be a conventional empire when the Ferengi themselves are so unconventional.
Timo Saloniemi