The big point between
Mass Hysteria and
Fervor is the cmc.
Fervor has 3,
Mass Hysteria only 1. Since it seems like you want to be as fast as possible, this may make a difference.
About the lands that enter tapped: My basic rule here is "If it always enter tapped, it need to have a significant effect". If this rule doesn't fit, I use a basic land in stead. The background is, that every land that enters tapped costs you 1 mana, because you can't use it imidiately. An example: You're at turn 3 and already got 2 swamps out. If you play
Akoum Refuge now, you would get access to red next turn, but at this turn you can only play stuff up to cmc 2. If you play a
Mountain in stead, you'll get imidiate access to red and are able to play stuff for cmc 3.
For 3+ colors I often use
Fellwar Stone and
Exotic Orchard. They are cheap, and since you're playing multiplayer, there are good chances that your opponents got the colors you need. If you want to invest a little more money,
Isolated Chapel,
Dragonskull Summit,
Smoldering Marsh and
Luxury Suite would do a great job. Btw, the red equivalent for
Tainted Field is
Tainted Peak.
If you really want to learn something about brewing commander decks, take a look here:
https://deckstats.net/forum/index.php/topic,42562.htmlSome of the more commander active players wrote some tips there, that should help alot in building (and trimming down) a deck.
I sadly can't say much about your vampires, I would have to make some research first. But if you look a little around here, there should be alot of edgar decks. I'm sure you'll find some more interesting cards in them.
Btw, I've just noticed
Victim of Night in your maybe board. depending on your playgroup
Walk the Plank could be an alternative. For black removal I like
Tragic Slip and
Curtains' Call (please notice the undaunted effect here).