Seems a little odd that Weapon Mastery doesn't appear to be incorporated into the profile here. Definitely a quick addition to make for anyone wanting a little more from these. 

I just dont see the difference between the Knight, Warrior Veteran and Guard Captain they are almost exactly the same statblock and with little to no flavor at all.

Well the Knight has better armor and saving throws, but lower HP. The knight also adds more damage in the form of 1d8 of Radiant.

The Guard Captain is stronger in almost every way, reflected in its higher CR of 4. Does more damage -- even with a shield -- better attack bonus, more HP, and better ability scores.

This statblock feels too generic. I get that it's supposed to be a little, but this feels like they overdid the simplicity.

Gained one hit die, increasing health from 58 to 65. Used to only know one language, now is forced to know Common and another one. 

Used to have a Longsword and Shortsword, now has a Great sword, which deals the normal damage, so it's not that great. Heavy Crossbow now deals twice the damage die, from 1d10 to 2d10, which is strange. Also gained the Parry reaction.

Overall, this statblock does feel a little too simple. It does have higher damage, but that's about it ignoring Parry. No fusion, but I wish there was more differences and uniqueness. 

Quote from Arsen_01 >>

Heavy Crossbow now deals twice the damage die, from 1d10 to 2d10, which is strange

 Also makes 2 attacks. 
It's not as strange as the knight, which also does 2 attacks, with 2d10, and a 1d8 radiant, "compensated for" by only having +2 to hit. 
But that's horrid game design, who told them that 2 attacks with +2 to hit and 2d10+1d8 was okay? 
It's way too damn swingy. 3-28 damage on a hit, 6-56 on a crit? 
And any player that picks up a 1d10 heavy crossbow with crossbow expert, no more -5/+10 attacks from sharpshooter, is going to feel wimpy by comparison, even if they have like +8 to hit.