First things first he will need to decide if its Best Man or Best Men - these days Bromance means that he may well not be able to narrow it down. Be assured that it does work and the pressure is off a little for the men when they are sharing the duties. I have seen it where they have been torn between their oldest friend and a work friend - whom they see every day. It does work, I promise. Speeches can be split and I am sure they would be more than happy to work together.
Do you need Ushers? If so who will they be? Are there any Brothers between you? Any Nephews who could take on the challenge? Or maybe a couple of friends. Ushers are important if you have a lot of guests so that there is some element of control when guests arrive.
One thing to bear in mind is that these people will be with your other half the night before or at least the morning of the wedding. There should be someone amongst the men that is organised, punctual and a calming influence across the brood.
In comparison to the Bridesmaids, the Ushers and Best Man/Men pose very little cost. After all its the suit if you are hiring or ties if they are using their own and a buttonhole. There is no bag, shoes, hair accessories.
You don't need to have equal number of Bridesmaids to Ushers in my opinion - that goes against choosing people because you want them and more to make it an even number.
Your husband should feel that he has chosen his men ultimately. This is equally as much of an honour as being chosen as a Bridesmaid.
Hope today's pearls of wisdom offer some help.
Love Katie x