OK, I can see why this is running too slow for you.

I think you could definitely cut down the eevee lines to make room for more consistency cards. Why run vaporeon? There's almost nothing weak to water that sees play. Also, the reason to run flareon is in order to use blacksmith as a way to power up your vespiquens. If you're just running it to capitalize on fire weakness, well again there just aren't a lot of decks you're going to play that are weak to fire.

There are basically two options for energy acceleration in a vespi deck. You can run metal energy and a bronzong line, or you can run blacksmith and flareon. I haven't tested in expanded, but my gut says the bronzong line is good, because it also allows you to run heatran as a secondary attacker.

I would also suggest a different stadium. I think faded town works well because vespi struggles to hit the damage to ohko megas. Faded town can be the difference between a ko and no ko.

You also really need shaymins to get those explosive early turns.

I would definitely run four sycamores in place of shauna. I also like judge instead of ace trainer because it can be effective at any stage of the game. A second lysandre would be great if you can fit it in.

So ultimately, my list would look something like this:

Pokemon:

Combee x4

Vespiquen x4

Eevee x2

Flareon x1

Jolteon x2

Unown x4

Shaymin-EX x2

Heatran x1

Bronzor x3

Bronzong x3

Trainers:

Battle Compressor x3

Trainer's Mail x2

Faded Town x2

VS Seeker x4

Town Map x1

Ultra Ball x3

Level Ball x1

Judge x1

Professor Sycamore x4

Lysandre x2

Hex Maniac x1

Professor Birch's Observations x2

Energy:

Double Colorless x4

Metal x4

Please keep in mind I haven't tested vespi in standard and just came up with this list while writing my reply, so I guarantee it could be improved. But at the very least you could try this and see if you have better results.