I love ByteBall, but also likely the required crypto intelligence. But AFAIK they are a relatively mature DAG tech, with oracles and smart contracts already working (P2P UFC betting being a relatively popular example). XRB is another promising DAG tech (which I currently own), as mentioned. I suggest you look into both if you're interested.

I'm big on DAG tech as I see it being the only form of crypto currency that I can buy my coffee with, without waiting so long for confirmation that it isn't worth it. Whether it can be a suitable replacement to blockchain though I don't know, it may be an apples to oysters type of comparison and one may have strengths where the other has weaknesses.

disclaimer: I own some of these so I'm not without some bias.

Thus far I've been pretty impressed with Raiblocks (XRB). Near instant (1-5 seconds depending on the wallet in my tests so far) and fee-less.

I'm pretty keen to check out the other DAG projects after this one.

The whitepaper (https://raiblocks.net/media/RaiBlocks_Whitepaper__English.pd...) is actually very readable, I really like it. Too bad it's almost impossible to buy right now.

The author is also a LLVM engineer who's worked for Qualcomm, Dell and AMD.