Tl:dr: I support trying option 3 and see where it leads. Being forced to wait up to an hour a day for an instance you can't just skip if you want the best gear is just not ideal, something that was changed in the later patch (4.7) for a reason. I also think it would revive real ow pvp on 81 instead of killing it. For details see below.
While I can understand that pvp focused players don't want to lose what little open world pvp is left on this server, I genuinely want to know where they can find real ow-pvp on garrison 81 during main EB time (18 - 21 servertime). During that time span the camp is constantly either green and filled with 3+ asmo alliances waiting for it to turn, or blue and filled with 3+ elyos alliances doing the same, only interrupted by maybe a minute or two when either faction gets their quests and enters at once. So that is one minute every 30 to 45 minutes where you can grief to your hearts desire and try to split alliances while for the rest of the time you just get spanked by a whole alliance in case you kill someone from their premade. I honestly don't get where there is satisfying pvp to be had.
The opposide would be the case for a npc circle with instances always open. You'd give premades the possibility to split up again, not being forced to enter with all the other alliances due to the fact that they wouldn't be able to enter at all otherwise. That means less league-like zerging, more group / single-alliance focused pvp like it used to be before covid when the server only had 2 or 3 EB alliances on each side. Then you'd really have the aforementioned dynamic that well-coordinated alliances are able to enter while other alliances might be split.