Ok, I’ve got some feedback after using solution I described previously.
First of all that thing stopped working the very next day. Given that I didn’t have SSH keys to login there, I couldn’t investigate why. I just dropped CloudFormation stack and created another one. So far so good.
Second disappointment is that I couldn’t make it work with Linux Mint. Network Manager’s PPTP plugin doesn’t work at all. I even installed client for L2TP/IPSec, but failed to get working connection.