Well first obviously all the leagues have the same roadmap, that's the whole point and has been ever since they started leagues. It's a gear reset, with one new gimmick. The gimmicks have gotten more complex over time and some are much more complex than others, but not sure what else you'd expect from leagues, it's a lot more stuff than D3 does, or most games really when it comes to repeated content. It has new monsters, new items, new mechanics.
Balance changes are too swingy and haven't really been that great, but they've forced meta changes several times, so in that regard, they've been successful, classes and playstyles that weren't popular were the most played when they were buffed. The melee rework has been good for more than cyclone, it just didn't make that many skills compete with the top end but overall the improvements are pretty big, it's not like melee was more viable before either, and if anything just cyclone alone was reworked into a much much better skill.
As for the devs getting lazier, not sure when that happened?
Look as I said in my post yesterday, I fully expect 4.0 will remove a lot of bloat and that there's definitely too much random stuff imo, but I don't feel it's at a point where it's actively turning people off, a lot of the superfluous content is literally just additional shit spawning that you kill and pick up some stupid tokens you then drop in your special stash.
And if you feel that content isn't worth running you don't have to either, I often skipped abysses if they went backwards last league, I skipped a bunch of corner breaches if they weren't chayula, I didn't bother opening essences stuff if they didn't have the big ones and so on. I also stopped running some of my missions at some points cause I had all the gear I wanted and there was no point in bothering with it. A lot of that bloated content is really super optional and you can skip it if you don't want to do it.
You can get tired and that's fine, I skipped some leagues in the past, sometimes in a row, doesn't mean that I won't come back to the game eventually. It's the same with FFXIV I play that a lot but I skip a ton of patches and just resub whenever a new thing releases and I'm excited to play, and the rest of the time I don't. Just wait until 4.0 if you don't feel like playing, a lot of people will still play. It will eventually die for sure but it's a long process for this type of game, especially when there's virtually no competition. And if by 4.0 you find that you still don't feel like playing, then you'll be done, but as long as there's new players to replace older players getting tired, it really doesn't matter. When you have people playing a game for 5+ years, you're always going to run into that issue. That's why people quit EQ, WoW, LoL, Dota, CS and so on.