Ok ... as far as I know ... people don't really do a lot in the Casual forum. Sad that the "fun" aspect of the game is not very active on one of the best Vintage sites in the world ... but then again ... a lot of people are only interested in winning those pieces of power and saying "screw the rest of you all, I got the Lotus, I owns you, I r 1337, u suxxors, etc etc"
As per my suggestions: I still think Pestilence/Shade is a bad choice ... when you only have 4 Drains and 2 Towers to gain life ... I insist that you change the shades. Reasons why I prefer to have Cemetery Gate over Shade:
1- Gate has inherently more defense, and against a lot of casual decks, creatures are the key to victory. If you can maintain your defensive posture, you can then deal with creatures as you see fit.
2- Gate only costs one more mana, and you don't have to pump him to save him, thus keeping your mana curve relatively low and you can still have additional mana to cast your other spells.
3- It has pro black, which saves him from Other black cards, namely Smother. Smother is an annoying little card that kills shade, and is used in many black decks for the control factor.
Additional suggestions:
In your sideboard include copies of Barter In Blood and Powder Keg. Barter is helpful when you have to go up against other creatures that your other spells can't usually kill, such as an Indestuctible monster. Keg is just useful ... no other comments required.
In your maindeck, consider Diabolic Edict, Isochron Scepter, Corrupt, and Withering Boon, and Consume Spirit as well. The emphasis behind these cards is so that you do not have to drain all your mana into pestilence. Withering Boon allows you to counter a creature at the cost of three life, but with Corrupt, Consume Spirit, and Drain Life, you can maintain your life total.
Also in your maindeck, consider Solemn Simulacrum, Extraplanar Lens, Promise of Power, and Skeletal Scrying. Solemn Simulacrum gives you a Swamp, and then another card when he dies. Lens can replace Bubbling Muck, and this also means that you only need 2-3 copies of the lens, opening another slot in the deck. Promise can have 2-3 slots as well, so that you can get a huge Demon token that flies and says beefcake every time he hits your opponent.
Note: I'm not saying that all of these should go into the deck, I'm just saying that these are some of the best choices for this type of deck. Having versatility and using your own combinations is the key to a successful deck.
If you need to look up a card:
http://gatherer.wizards.com