Does this still blend in well with normal HTTPS traffic?
There are some useful ideas from SoftEtherVPN, BitTorrent, Yggdrasil Network, and Tor you could borrow, if you're looking to improve this. The ideal tunneling solution, which doesn't exist yet, is one that not only evades DPI, but also onion bounces you through nodes in a decentralized ad hoc network, and does automatic node discovery.
thanks for your work