So, you need the 5 Str for your shotguns, but 4 or 5 is generally a bad number for a stat to be at unless you have a specific reason to do so. It's better to min/max a bit and pull that Dex and Con down to 3 each and free up 4 more points. Then you could get 7 Will and still have Blitz, if you wanted.
I wouldn't get Blitz. If you're willing to pick up psi as a support set, then I'd dump Agi entirely, in fact, because psi haste is so much better than Sprint and Hit and Run and Blitz combined. Well, I might keep 6 Agi for Sprint if I had nowhere else to spend points, but I'd rather put those points into Int and Will if, like you, I wanted to have a good amount of Persuasion on tap (you want to be able to buff up to a little over 100 effective skill to hit all the checks in-game).
If you were willing to do a little bit of gear shuffling and were willing to do your crafting back at home where you get your skill bonuses, then I'd think you'd do much better with a setup like this:
http://underrail.info/build/?HgUHAwULBwjChyMAAAAAUE9LAEZfXyJHXwAtwqBGRgA8KwEoJFM1KcKwwpYqwod-M0vCnOKitQLfvwThis'll get you all your Mercantile thresholds and all your Persuasion thresholds, while also allowing you to pick up Grenadier and Quick Tinkering, both of which will allow you to control the battle field significantly (through more frequent grenades, obviously, but also through setting down traps mid-combat in case things start to get out of control), while also giving you just enough Psychokinesis to get the electricity trap, which is also really great for chokepoint control. It also pulls back your overspending in Lockpicking and Hacking so you have a few more points to go around. This is a more min/maxed build than what you made, but it'll do everything if you're willing to juggle a few things here and there. You can still make all your gear, your Mk IV grenades/traps, your Super Soldier Drug while fully buffed, and can make your everyday consumables without any buffs. This is, to me, a very workable level of min/maxing.
edit: build link modified for new Character Builder URL