[quote]Why the hell did the design for UNSC frigates change?[/quote]They didn't. The Stalwart, Paris, and Charon all look like their Bungie iterations. The only one that doesn't is the newest model, the Strident. The Forward Unto Dawn is an artistic exception, but canonically, it looks like it did in Halo 3. [quote]How did Johnson get off the ring?[/quote]He and some Marines and an ONI agent were able to hop into a Pelican, just before the ring detonated. [quote]What happened to Jun according to canon?[/quote]He escaped Reach through unknown means. I speculate he might have escaped on the Aegis Fate. And later wound up as one of the key member on the SPARTAN-IV program. He hand picked the initial members, and went on to train them. [quote]Is Halsey returning in Halo 5?[/quote]It's too early to say for certain, but she will definitely be involved in future games.