Umbreon-I would replace Toxic with Charm, and Bite with either Moonlight or Rest. Even with STAB, Umbreon can't do a whole lot of damage with Bite when it has such a low Special Attack. Attach Leftovers.
Umbreon
Charm
Baton Pass
Mean Look
Moonlight/Rest
@Leftovers.
Tyranitar-Very good, standard.
Porygon2-Since you have a lot of Special Attackers, it wouldn't be a bad idea to maybe use a Cursegon instead of a special sweeper.
Porygon2
Double-Edge
Ice Beam
Curse
Recover
@Leftovers.
Electabuzz-Great moveset, standard.
Alakazam-Replace one of the elemental punches with Thunder Wave, and put Recover in the last slot. Attach Leftovers.
For your last Pokémon, I would go with Suicune. It will be a little better against Snorlax and Machamp then Skarmory, as Machamp and Snorlax sometimes know Fire Blast. Your team already has the 3x Fighting weakness, so no need to make Machamp potentially more dangerous to your team then it already is. Your Suicune moveset is very good, just attach Leftovers. If you decide to go with Skarmory, replace Steel Wing and Double Team with Curse and Rest, and attach Leftovers.
Overall: Your team has a 3x weakness to Fighting (like you already mentioned.) and Bug types. So, you will want to be careful around stuff like Machamp and Heracross, because they could present some problems for your team.