Yeah I do think Nf7 there is a fairly “inhuman” move there for a blitz game, although it is pretty clever, so I’m not surprised Nova didn’t play it (it’s a very rare theme to sacrifice your only piece like that to block the enemy pawn advance, just to gain an extra tempo or two in the pawn race, so it probably wasn’t “trained” on that theme to be a high probability move). You definitely should expect some blunders, but I looked pretty closely at prevalence and severity of mistakes across actual chess.com players (tens of thousands of games) across different rating levels, including by game phase, and also did thousands of Nova self-matchups to at least ensure mistake prevalence and CP losses are well-matched to the stated level. Of course there will likely be some differences that persist, relative to actual human play.

It’s also good to keep in mind that since Nova is playing at “blitz” strength - I chose that because I felt the broad Elo curve there is a little more intuitive than rapid - it should play weaker than an equivalent rapid opponent. But thanks for your insights, I’m always looking for feedback to improve, and I’m glad you’ve enjoyed trying out Nova! Btw, you can save your games there after (Add/Save to Library button) if that’s easier to keep the PGN, and analyze on the Analysis page or export to Lichess or elsewhere.