Yes, the length of the pikes is a bit of a problem. The original length is from 4,65m up to 5,6m depending on the nation to who they belong. For example it is said that the swedish used longer pikes because of their experience figthing polish winged hussars in the 1620. The imperialists used pikes from 4,65m (15 feet) to 5m (16 feet).
So there was no standard length at all.
A pike of 5m would be 88mm long for a 30mm figure. The pikes of Mr. Beier are around 80mm.
So they would fit a pike of 4,65m.
But there are some acount saying that the soldiers shorten their pike themself to make them easier to handle. Of course without premission of their officers.
So for my opinion pikes in differnt length are okay when lenth stays in a certain frame.
You are right that some older editor´s pikes are very short. Ochel and Wünsch for example. Generally I prefer the longest pikes like Bock Sivhed, Fritz, Wagner... which are up to 100mm. But these new figures don´t look to bad with them and I´m very sure that not all pike in the thirty years war had the same length.
Christoph