1# So I like to start new mercenary units around the Lance to Company level. Generally, with some infantry and logistics in support. If the unit it flush with cash and tech then maybe they have a Lance of Aerospace support as well, or even a dropship.
2&3# Given the many campaigns I’ve played, I really have enjoyed putting together a unit in the 3rd Succession War era, and then playing out a great campaign. This way the unit’s history is organic, and you get to have some great long campaigns. However, many of my units come to a horrible end with the Clan Invasion, or the Jihad. And I have played several campaigns where we were throwing together units for the Chaos March, Civil War/Jihad eras.
4# This one is a little hard to narrow down, but I do tend to play a lot of ex-Lyran or Marik characters when throwing this kind of campaign together. But mostly it just depends on what I feel like the character fits.