Crota's End was fun for quite a while. Also I think the Deathsinger counts as a second boss to some extent. She didn't always melt like butter like she does now. Crota didn't go down in one sword, or even two swords unless Sword Bearer timed it perfectly. You had to deal with the ogres. It was a lot 'more' of an encounter, despite the abyss and bridge being a cake walk.
Also, the fact that there were two exotic drop chances and people were still chasing the Gjallarhorn had a lot to do with it. You didn't get infinite exotic chances with 3oC like you do now.
I really enjoyed Crota's End in its prime. It was great finding a group as a sword runner and hearing that they've been at it for an hour or multiple attempts that week and helping them get it done. Crota's End was great for the Destiny 'hero fantasy' for a long time if you could run the sword. I might have had more fun with that than with Vault of Glass. You could really stand out as a good player and asset for the team in that sense. In Vault of Glass you can do everything perfectly, solo a conflux, get the most oracles, run the relic, lead the way through the maze, win at the jump puzzle, solo the gatekeeper on mars, kill every Oracle on mars side while holding the relic and cleansing, hit a relic super on Atheon on the way to the platform, basically do every job perfectly, and you still don't really stand out in the way you did on Crota's End as a sword bearer. You were fucking center stage.
I get the criticism and that it hasn't held up well, rock band drum solo and all that, but Crota's End was a fun fucking raid for a long time and it feels like noone remembers that.