Since you're weak to Bug, Ghost and Dark, a Steel Pokemon like Heatran can help you here:
EVs: 248 HP/252 SDef/8 Spe
-Hidden Power (Ice/Grass)
-Stealth Rock/Substitute/Taunt/Flame Charge
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb/Air Balloon
Thanks for your advice! :D I've tested out both sets you suggested and the Timid/Life Orb set worked the best for me. Heatran is exactly what I was looking for since it benefits from the sun and can take the Ghost and Dark type attacks aimed at the rest of my team. The sun does weaken Starmie's Hydro Pump but I haven't had a problem with that yet. As for Espeon's Morning Sun being useless when Ninetales is KO'ed, that usually doesn't happen often but what other move should I replace it with?
Wouldn't it be better to switch Tyranitar with Heatran since Heatran would benefit from the sun? I like the idea about switching Hidden Power to Fighting though. I have had trouble with Dark types taking Espeon out because I couldn't do anything.