It supposedly supports fancy features, so I'm curious to see how those look, they also say it's got top of the line speed, so maybe a screencast with side by side of reference terminal emulator (xterm?) and ghostty displaying heavy throughput output to see the smoothness goodness
No terminal emulator ever should affect the performance of the rest of your system.
No idea honestly, people are saying that certain heavy output programs might just slow down the execution of other graphics related processes because text is usually expensive to draw, haven't tried it myself