Agree.
First, when you're talking best MC of all time, group work is included. It ain't the best solo album catalog ever. It's who's the best man on the mic in all iterations. So that includes his contributions to group albums & co-starring w/ Rae on both Cubans, where Ghost was such the standout on Cuban Linx that he leapfrogged mid-90s Deck to drop an album.
Second, Ghostface switched his style completely on 4 successive albums and remained for the most part consistent. Ironman was continuing his style from the guest spots & Wu solos, then he went into his abstract style on Supreme, then abandoned that to have an album of all concept & story tracks on Bulletproof Wallets (The problems with that album were all production & songs kept off/ changed for sample clearance but that is one of Ghost's best performances on the mic.) That album's reception & criticism had him step back lyrically on Pretty Tony but he rebounded with Fishscale which compiled all the styles he'd done before. And his Supreme Clientele style was so iconic that people a decade & a half later talk shyt about 'Ghost not making sense' when he dropped that style back in 2001 (meaning you can easily dismiss them as they're not even listening).
Third, The importance and influence of Ghostface. There's the influence as part of Wu as a whole. There's the influence of Cuban Linx, which blows up mafioso rap and inspires It Was Written, Doe or Die, Reasonable Doubt, etc... There's the influence of Supreme Clientele, which was a sample heavy album in the keyboard era when people were writing the sample off as dead. SC was the blueprint to the Blueprint's return to samples and inspired the next 5 years of production:
- Kanye West
Fourth, you've got an ear for beats. Ghost has stayed once of the most consistent emcees in the game who, while rapping over many different types of beats and never limiting himself, has always maintained a tremendous sonic backdrop to his rhymes. While there are arguments for better people on the mic, I don't think anyone else on the mic tops Ghost's ear for what he's rhyming on. And that's huge. Take whoever your favorite MC is and put him over Ghost's instrumentals and it's an immediate upgrade.
Fifth, you've got flow
you've got storytelling
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you've got raw spitting
you've got emotions
you've got originality
Opinions are whatever and everyone's lists will be different, but I bet if you got a top 10 without Ghost, when you break it down some of those people aren't seeing Starks.