Hello Lettuce,

1) There's a ton of different warbands on that list. Many warbands were never meant to be balanced with all the rest so you can expect imbalance to show up depending on what the players decide to use. The people in charge of Mordheim gave a list of "official" warbands that show us the ones they thought worked the best: http://mordheimer.com/warbands/official.htm

2) According to the rules as written and the picture in the book, no. The intercepting model needs to be entirely within the charge path of the attacker. This is one of those grey areas that people usually ask about, you're always free to use it however you think it should work.

3) I don't use any house rules for armour but that one seems ok. Dwarfs can get a 2+ armour save easily (gromril armour + shield) but critical hits will still get past it.

4) You are always free to create a new warband whenever you want to, even the exact same one. At the start of a league this is usually what happens in my groups. I have never done it myself, though.

5) That's a common and pretty good house rule. I don't think this alone will make shields better than a second weapon but if a shield now gives a 5+ armour save (covered by your armour house rule?) then it will be a much tougher choice.