Personally, I can't imagine cutting any Vesuvas. It's one of the most powerful and flexible cards in the deck. And it's especially useful against graveyard decks; I've won a lot of games because Vesuva effectively means that I have 5x maindeck Bojuka Bog. And copying Posts is good.
If you're having trouble with tempo decks in your meta, take a look at my build.
Main Deck (61)
1
Emrakul, the Aeons Torn2
Kozilek, Butcher of Truth1
Ulamog, the Infinite Gyre2
Ugin, the Spirit Dragon2
All Is Dust4
Ancient Stirrings4
Candelabra of Tawnos4
Crop Rotation4
Expedition Map3
Exploration3
Pithing Needle2
Sensei's Divining Top1
Bojuka Bog4
Cloudpost1
Eye of Ugin8
Forest1
Glacial Chasm4
Glimmerpost1
Karakas3
Maze of Ith1
The Tabernacle at Pendrell Vale1
Thespian's Stage4
Vesuva
SIDEBOARD (14)
3
Krosan Grip4
Mindbreak Trap1
Oblivion Stone4
Sphere of Resistance2
Surgical Extraction
It takes a bit of practice -- especially mulligans and land sequencing -- but it has very strong tempo matchups (including BUG Delver, which I always see people complaining about here). Maze is important in those matchups, but I also use Exploration to mitigate the tempo loss from the extra land drop it requires (and it can lead to some absurdly explosive starts). But my local meta is normally very Delver-heavy, and I've been preying on those decks for a long time.
Another thing that I do to fight tempo decks is drop fetchlands entirely. Now, I'm monocolored (and really just splashing green at that), so fixing colors just isn't as big a deal for me. I also play Ancient Stirrings instead of Brainstorm, which doesn't need shuffle effects for maximum value. But, even though I do play SDT, dropping the fetchlands means that Delver is never going to T1 Stone Rain me with Stifle. (It also means that I can consistently cast Krosan Grip through a T1 Blood Moon on the draw.)
Another thing that I think helps me against tempo is running the full 4x Crop Rotation (although I see you already do that). Being able to effectively Stifle their Wastelands is critical. And having the full 4x helps when you're running Maze of Ith because you can easily upgrade it into a Post (or whatever) in matchups where Maze is a dead card.
But just running a higher land count -- including Vesuvas -- makes you less vulnerable to early Wastelands. If they Waste you on T1, they're not playing a threat. If they Waste you on T2, they're not playing a Goyf, so the worst-case scenario is just a blind-flipped Delver. And in each of those situations, having more Posts in your hand to play (including Vesuvas), means that you're just trading more-or-less one-for-one on tempo. One of the reasons that I like Ancient Stirrings so much is that it lets you use non-Wasteable basic forests to dig so deep to find what you need (land, Maps, Candles, Needles), which makes it much easier to recover from early Wastelands.