I will be the dissenting voice here: I would not dream of attempting this connection on separate tickets! Especially not without ascertaining in advance that baggage will definitely be checked through on separate tickets, which is by no means guaranteed. I understand that some airlines won't even do this now when both flights are with the same airline.
If you want to do this... contact Air Baltic before you book your flight, and if they say baggage will be checked through on separate tickets get it from them in writing.
If you can't check your bags all the way then this is going to be extremely tight, and unless your ticket home is fully flexible then you're taking one hell of a gamble because there is close to zero time to play with. (You mention 20 minutes somewhere, which is almost as close to zero as you can get). Statistics mean nothing if something goes wrong on the day you want to travel, and there are so many things that can go wrong.
Some of my recent flight delays have been due to...
- weather, including early-morning fog
- staff sickness (having to wait for a replacement pilot to arrive from the other side of town)
- technical problems (even the smallest technical issue will take half an hour to fix and sign off)
Any of these could happen, and cause you to miss your connection - and then what?
My personal minimum on separate tickets is four hours - and I would allow considerably more if the onward flight is a long-haul one.
I would travel the evening before and stay overnight.