You may be interested in
my comment about Byteball's smart contract language.
What about Iota, the other (and first) DAG coin ? Lot of press at the moment
Start reading
here.
I also wrote recently:
There is only PoW, PoS, DPoS, and DAGs. Actually the only DAG that is sound is Byteball, but it has the same problem as Casper, TenderMint, and Cosmos in that it can get stuck and require a hard fork to unstuck. Nothing else so far...