this deck is a little bit slow out of the gate but if all goes well it absolutely explodes at around turn five or six. my fav. tricks so far have been to 1.) imprint lodestone golem, contagion engine or blinkmoth urn with Prototype portal and 2.) Rite of Replication (with kicker of course!) either Master of Etherium Tidespout Tyrant or Arcbound reclaimer
31 land and no artifact sources or ramp spells? You're just begging to be manascrewed. Try 37 or so lands, plus cultivate, kodama's reach, skyshroud claim, or explosive vegetation.
Also...Memnite? In EDH?
also, i used to have a lot more mana (38 lands) and found that i really didn't need it, i have had a couple games where i got screwed but overall its been fine on mana, if i get really stuck for lands i usually have enough draw power to get one or more mana sources or search sources out. however i will look into your suggestion and try a few more lands to see what difference that makes.
Memnite's legal, yes, but it's also bad. The only possible reason I can think of to run it is if you're planning on pulling crazy storm or Quest for the Holy Relic shenanigans. Otherwise, I'd rather have a basic land. Ditto for the 'thopter.
As for mana, 31 lands in a 100 card deck is like running 18 lands in standard. Not advisable. Granted, EDH has generous mulligans and the games go on long, giving you a chance to draw out of land-poor hands, but I would still never run less than 35 unless I had a very good reason to.
Memnite and thoper are in there because there is a decent amount of artifact drop abilities that benefit from them, and there is a great combo of artifact drop with them two and the Tidespout tyrant... (Tidespout Tyrant, Inexorable Tide. Memnite and thoper, or with Mycosynth Golem and any two artifact creatures with mana cost less than the number of artifacts in play.)
So they add counters to Golem Foundry, can be sacced to Arcum, and give you an infinite proliferate combo with Tidespout Tyrant and Inexorable Tide in play.
That's not much.
If you're absolutely in love with them, at least run Trinket Mage so you can tutor up the weenies so you only need Tyrant + Trinket mage to get the infinite shenanigans started.