IS anyone else having an issue with HVT missions spawning all 8-9 of the same identical mobs such as: all shotgunners or all snipers?
Yes.
This has been an issue since S&D were introduced.
Massive needs to make sure their NPC selection algorithm (or whatever) adds more variety because it doesn't matter what you are using if the game spawns 9 shotgunners, you will die in a few shots from being overrun even in Week 3, where TTK and TTBK have been almost perfect.
I understand it was intentional to do this for some S&D. The grenadiers in particular are a *****.
I actually quite enjoy it when that happens, you are forced to change the way to combat them to cope with the numbers of similar types of enemy's. Grenadiers, keep moving from cover to cover as if you stay still you will be blown up. Shotgunners are the hardest but feel like you've accomplished something.