Finally managed to solo Machamp!

There is a big difference in survivability. DP is only 10% weaker than CC but is spammed almost twice as often. With your team you will have to dodge with the Espeon and zams.

There is a big difference between Close Combat and the other 2 charge moves in terms of difficulty. The other two being about on par with each other - Heavy Slam being harder due to it's lower cooldown - and Close Combat being much easier.

Close Combat has slightly higher damage per use but it deals much less cycle DPS because it's total damage per 100 energy is lower and the other movesets are also less predictable because they can be used anywhere from 50 to 100 energy.

Like once the boss uses Close Combat you know you're safe for a while to spam Confusion whereas with the other movesets, every Confusion used puts you at risk of a missed dodge, unless he's just spammed 2 in a row, so personally I prefer Psycho Cut on Alakazams as you're more consistent with how many charge moves you can put out before fainting when you can't miss dodges.

Even in Cloudy weather, Close Combat movesets are still less difficult than Heavy Slam movesets in extreme weather / without weather bonuses in terms of damage dealt and time to win and that's assuming perfect dodging.

In reality Heavy Slam is more unpredictable so you're more likely to miss dodges than against Close Combat so the actual time compared to the expected time is going to be even slower.