Hi Chris!!
Heracross-To get the most out of Endure/Reversal, you will really need to have an Agility or two Baton Passed to Heracross. Sleep Talk and Rest has become the standard for Heracross instead of Endure/Reversal, and it works really good. If you keep the Endure/Reversal set, then attach a Miracleberry. If you use something else, then attach Leftovers.
Jynx-Smoochum learns Sweet Kiss at Level 9, and Jynx learns Lovely Kiss at Level 9. If you catch a Jynx from the Ice Path, it will already know Lovely Kiss. There is another way to get Lovely Kiss on Jynx, but it isn't very convenient. It requires Pokémon Stadium 2. In PS2, If you neat the Johto Gym Leader Castle with your own Pokémon, than Lance will give you the chance to teach one of your Pokémon a previously learned natural moves. (no Egg moves) move that the Pokémon has forgotten.
Jynx
Ice Beam
Lovely Kiss
Mean Look
Perish Song
@Leftovers.
Raichu-Surf is a very nice move to have on Raichu. (Surfing Pikachus can only be obtained in Pokémon Stadium 1) HP ice and Reflect could work for the last two moves. Another option for Raichu would be Endure/Reversal, if anything else, it could surprise a Tyranitar.
Xatu-The moveset isn't all that bad. Drill Peck would be great, but Drill Peck requires breeding. If you really don't want to do breeding, then perhaps something like Giga Drain would work, but it wouldn't really be as effective as Drill Peck would be.
Xatu
Drill Peck
Psychic
Confuse Ray
Night Shade
@Leftovers.
Primeape-When a Pokémon can be either female or male, then the females will always have lower attack than the males of the species. I was just letting you know, since you referred to your Primeape as a female. However, breeding is required to get some of the better moves on Primeape, like Rock Slide.
Primeape
Cross Chop
Rock Slide
Meditate/Psych Up
Attract(if you keep a female Primeape)/Rest
@Leftovers.
Now, for the last Pokémon, if you want to go with a Smeargle, you can't really rely on attacking moves, even to cover weaknesses. Smeargle's max attack stat is 138, and it's max special attack stat is 138, so it can't really do a whole lot of damage, even against something that it's moves would have a type advvantage against. If you want to go with a Smeargle, you could try something like this.
Smeargle
Agility
Spore
Spikes
Baton Pass
@Leftovers.
This Smeargle is more of an annoyer/supporter, it also keep the option open if you want to keep Endure/Reversal on Heracross, since it can pass Agility to Heracross. If you are looking for a different Pokémon other than Smeargle, then maybe something like Tyranitar or Miltank would work good
Tyranitar
Earthquake
Rock Slide
Crunch
Flamethrower/Fire Blast
@Leftovers.
Miltank
Body Slam
Curse
Heal Bell
Milk Drink
@Leftovers.
Overall: No 3x weaknesses, which is very good. For in-game purposes, your team is already very good. For battling with other people, with a little bit of work on a few of the movesets, it will definitely be a very nice UU team. It's nice to see some UU Pokémon being used, instead of the same, usual Pokémon. Nice Work!!