I would've always preferred to stop at LoY, personally.
I thought frogs were pretty awesome, but I didn't like the lazy implementation of them taking over Grobb, and everything that it entailed with trolls being forced out and the changes to starter cities and starter areas that resulted. Of course there's those people who will run around like a damn Christmas tree, or in all pink with the armor dye system, which I always found kind of immersion breaking, but to each their own.
Apart from that I was/am very pro LoY. The expansion brought a lot of great QoL improvements and also completed the development of Odus which started with the release of Warrens and Stonebrunt. The way in which it was released (small content update instead of a large expansion) was basically experimental, and the fact that they never released another expansion in that fashion really speaks for itself. At the time it seemed like a cash grab to sell people QoL features that should have been in the game for free at that point.
LDoN, though I really enjoyed it when it came out as I was playing with 1-2 friend most of the time, I think was a very bad design decision by Sony. Apart from the augment system, I really don't have much positive to say. It was an OK expansion if all you wanted to do is run the same instances over and over again with a small group of people, but really put an end to grouping as we knew it.
The raid content was terrible, and itemization with adventure points kind of forced/funneled people into instancing all day long instead of exping in PoP. While instancing made a lot of sense in PoP with the Plane of Time, the way LDoN implemented it really for dungeons really ruined them. I also disliked the fact that you had to run through (sometimes) multiple zones to get to your dungeon, and the ridiculous difference in difficulty between the different adventure camps. All in all, it was very poor design and just seemed too random to me.
GoD was very bad, the flagging system was a major pain in the ass and content was unfinished. It basically repeated all the bad design (flagging) of PoP and put a magnifying glass on it.
If I had to rank the stopping points for a server it would be:
It's only natural that people hit a ceiling and want to progress, PoP is really sub par unless you are playing in a dedicated raid guild, but if we are being absolutely honest this didn't really get better until OoW.
You also have to understand that this server's vision was to get to PoP and then work on making the server the best it could be for this era, since there was no more rush to bring out new content, I totally understand that the Devs want to stick to that plan for the time being.
This isn't a big surprise either, so if you somehow feel surprised about not being able to continue progression, you should have thought twice about rolling on this server. I mean it is right there on the Start Page. What is pretty unacceptable is the attitude of some people here, who act like entitled children. You know who you are.
Look at it from a dev standpoint. This stuff takes a lot of work, and the bug forums are full of stuff that could really use some attention. I think that should be the focus for a while, now that Plane of Time is released. Which to be honest only happened so early because of pressure from people rushing through content.