First, I do not agree that “face balanced” putters are just for those types of strokes that are “straight back and straight through”. I know others in recent years have attempted to categorize them that way, but again, I do not agree. I know and have worked with many players that use face balanced putters that have different degrees of arc in their stroke. In short, a face balanced putter is a very balanced putter in which the head is more stable through the stroke, for any type of stroke. Generally speaking, the instruction on toe hang for those that prescribe to it is that the more arc you have in your stroke, the more toe hang you need. The facts are that any arc in the stroke means the club face is only square to your target line at one moment in time. So, you better be consistent in your ball position, address, etc. That is why eyes over the ball, hands below the shoulder sockets, with very little if any hand movement etc. is the best position and technique to create the most consistent stroke. That being said, there is some arc in most all strokes and if a player believes through what they see at address, what they feel, and what they see with regards to how well the ball starts on their intended target path that a certain amount of toe hang is beneficial, then they should use that type of putter. To determine that does take some time, expertise, honest self evaluation and maybe even a lesson or help from a qualified fitting professional to dial it in. That is just my opinion based on my experience.
With regards to slant necks, we have options that can be used with some of our putters. The link is below. I do not have exactly how much toe hang, or how little, there is with each combination, but generally with the mallets we have that can use these hosels, the 1″ will produce more toe hang than the longer hosels. In our Pure Track line, the PTM1 would have the most toe hang, the PTM4 is more a traditional plumbers neck and would have slight toe hang, the new Center shafted PTM-5CS is a center shafted mallet with slight toe hang and the PTM-5, when used with a 1/4″ to 3/8″ double bend will be face balanced.
Hope this helps.