I believe less Grievous is more. He’s supposed to have a fearsome reputation both as a fighter and as a tactical leader, but the show (especially the earlier seasons) doesn’t deliver on that. So by cutting the episodes where he doesn’t do crap (like Duel of the droids) you can make Grievous feel more like a mysterious presence, building more of a mystique around him that pays off whenever he does something badass or crucial (i.e. wiping out the Nightsisters, attacking Kamino, masterminding a terrorist attack on Coruscant, etc.).

Don’t know if you’re in need of feedback for your ranking system but off the top of my head I can think of these:

Vital: Mandalore, Nightsisters/Maul, Ahsoka’s trial, Order 66
Important: Citadel, Umbara, Onderon, Sifo-Dyas, Yoda’s trip to Moraband.
Desirable: Zygerrian slavers, Obi-Wan undercover, Heroes on Both Sides (probably one of the better-executed political episodes and lays some groundwork for the Onderon arc and Lux Bonteri’s story, but the follow up episodes pale in comparison)
Objectionable: Duel of the droids, D-Squad, The Disappeared (JarJar and Windu).

I’d like to se the Malevolence arc included; it builds on the early relationship between Ahsoka and Anakin, it establishes Ahsoka’s bond with Plo Koon which is a nice touch, Grievous is a decent enough antagonist that actually gets away with destroying some medical ships, etc. Maybe the last episode where everyone infiltrates the cruiser could be abridged, but it’s overall one of the better arcs of Season 1.

I guess including Ahsoka’s walkabout is necessary for her character development, but that arc has terrible pacing (not enough story to fill up four episodes). It should be framed as a typical Mando side-quest story where the protagonist meets the character of the week, agrees to help them, then right to business. Hopefully avoiding detours like the rogue droid on Coruscant and the entire third episode.