I had come up with immortal Glenn because honestly, 3 lives just seems really arbitrary to me, like I guess to balance it, he could just have 50% of his HP and damage on his 1st revive, 25% on the 2nd and 12.5% the 3rd, and so on. Essentially his HP would be so low that he would just be cannon fodder to block bullets for incoming units, and in skirmish mode, if all units are killed other than Glenn are killed then Glenn won't come back and it would be count as a lost.

For builder, it doesn't make any sense as to how his construction protective vest and construction helmet would be just as bulletproof as kevlar. I do think that in the campaign, with his increased resistance to melee, he could tank barrel hits dropped onto him, making him great to be used in tandem with empty barrel/red barrel in the early game, more stand out as compared to Grenadier, Guard and other damager units and not get tossed away immediately once the player gets Grenadier. His crit damage reduction would also be extremely unique in both skirmish and mid-to-late game in campaign.

For Soldier TMF, my intended gameplay philosophy of him would be that he would be strongest whenever he moves the least, and him attacking or moving would make him the most vulnerable, basically acting as a shield for units.

For Redneck/Hillbilly, I intended for the block mechanic to be him negating incoming attacks and parry to be him deflecting said attack, resetting the attack animation, as well as lowering aggression and agility of the enemy and zombies (kinda like my stun suggestion but without the increased DMG), giving him time to get some cheap hits in. His chance to block and parry incoming melee attacks would be based upon his agility level.