I think the job decides the size of the crew. In your company jobs are priced by the man hour, so if I get a 10 hour job I 5 hours to finish with 2 guy and just over 3 with three. I have found that on large removals 3 guys work great, but If were doing a bunch of small trim jobs I have a easier time getting done in time with 2. For example, if i get a 4 hour trim and I have thee guys I can waste up to an hour or more just in travel time. By the time I get started I have less than 1 hours to finish the job. with Two guys I can spend 1 1/2 hours in the same tree and still finish in time. All that being said we have ten guys on are tree crew, so we can mix and match to suit the jobs. If You are only going with one crew than you have to decide what percentage to big jobs to small jobs you do. If you do a lot of big jobs go with more guys. If not than just stay with 2 you can do a lots with 2 men, and it cost you less if you have any down time.