There's too many problems with this map, so I'd like to offer a solution that would hopefully meet in the middle and solve A TON of problems, both gameplay-wise and aesthetically.
In general, "wrap around" path would be shortened a little. To illustrate this, I shrunk HALF (bottom half) of the picture's height in Photoshop. This by itself did a great job at connecting the vehicle path with the walking one.
The next thing I did is decide to put the vehicle path underground, and completely REMOVE THE BRIDGE. The bridge really looks like SHIT, and there really isn't any way to fit it in well. So, by putting it underground, you can instead have SUPPORT RAFTERS LIKE IN HALO 3 (black lines on drawing) that can be used instead of a bridge. Maybe a hole in the ceiling of the underground vehicle path would be cool too so you can let some light in. (I REALLY WANT TO EMPHASIZE THE FACT THAT THIS IS AN UNFINISHED RING!)
The middle of the map would be very much like the forerunner hallways you see in Assault on the Control Room (and here in Halo 3). They're tall and have a lot of open space on the side of them for cover and passing by. The hallways would flow into a center area that would contain a PULSE GENERATOR which you can fight around. The structures in the room will provide the cover we're all familiar with in campaign, so it would be just fine. You would also have the option of going left, right, or directly through the center of the room to get to the other side of the tunnels.
(btw, the hallways would be the extra-wide hallways that have the offshoot to the side of them, like the hallway before you get to Johnson's Warthog at the end of Halo 3. (indicated in dark blue))
The center room would also be unfinished, though, almost like in Halo 3 with the terminal room. It would have a hole in the wall which would flow into the vehicle path. More specifically, it would allow a player to walk directly on to the support rafters I was talking about earlier (that's how you would get up to them). You could also drop down to the vehicle path if you want to from there.
If you do this, you will absolutely have an awesome map. It would be almost perfect, and you wouldn't need that STUPID door syncing and teleporter shit.
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