The flame thrower/sniper is definitely a must if you will do any tournament play, almost always see one in tourney lists.
The tank hunters depend on whether or not you want the ATR team, you can make the suicide man from the standard infantry unit, I did one with the tank mine on the flagpole and two others with satchel charges. You’ll want at least 3 as the rulebook allows you that many that count as 1 AT unit in a list. They’re your best AT weapon for the cost once you learn how to use them.
I have 3 Lt. Mortars, don’t often use all 3 but when you can spare the points they are a great weapon and as already noted they can fire at a different target than the rest of the squad so you have the possibility of putting pins on 2 units with 1 command die.
The Chi Ha tank comes with everything you need to build both turrets, the Howitzer and the ATG. There is one piece that you need for both turrets and they only give you one. I was able to make a second one using blue stuff instant mold to make a mold of it before I put them together and milliput to create the piece. Wasn’t perfect but it worked well enough that I have both turrets available for my tanks. Generally early war I use the How as your opponent should have Stuarts, late war I may use the ATG depending on whether or not I think my opponent will have a Sherman.
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