Hmm... Do you have T-Mobile? I think that might be the only reason I'd recommend getting the Plus now. They have it at a really nice discount with a trade-in (trade in something cheap) and you can Jump to the newest one once it comes out. That's exactly what I just did (and will do - I came from a Nexus 6). Otherwise though.. Man, I'd say to wait. This device with maybe an extra gig of RAM and an even better camera? How could it not be a 10/10?
Don't get me wrong - if you get this now, you're absolutely going to love it. But if you're the type of guy who bought the OnePlus One, you probably like having the newest/best phone. And... It would suck to have "phone envy" so quickly after buying your phone.
But man... These phones feel SO much more polished for whatever reason. Hardware + software.