Is there a reason why you

Is there a reason why you can't have a larger radius? 22 seems awfully tight even for a branch line. 

I suspect many radii to come

So the branches will be just for operations purposes. My overall basement are is 22'x24' and I was originally going to just do around the walls. Then I thought about operations and I thought that a tighter radius will allow me to do more things in a tighter space. I am asking this questions, just because I want to see what the overall opinion would be.

 "I thought about operations

If 22" is required to get the branchline operations you want  then go for it. Lots of layouts have been built with 22" or even 18 " curves . Should be no problem for most freight cars and 50 foot cars and 4 axle diesels or small steam will look fine on it. Keep the grades as flat as possible as tight radius and steep grades double the problems of either alone.....DaveB

I suggest you lay some spare

I suggest you lay some spare track on a board to see how your rolling stock looks on it. Sometimes even a short coal car on such a tight radius can look very non prototypical to the point of looking toyish especially with a loco on it. When I see HO scale rolling stock on such tight radii, it looks like and reminds me of the old Lionel Trains on tight radii. To each his own. 

2 cents worth

I  would  use 4 - axle  units  on the branch  lines.  6 - axle diesel units don't  like tight curves.

Ken  

coal branch

Yes, 22 in radii would work.  Keeping in mind the 4-axle diesel comment earlier, a string of hoppers snaking along tight curves is very common with coal branches.  In fact my RR's focus is exactly that and uses GP-7s & GP-9s, and steam loco such as 2-8-0's and 2-6-6-2's.

Rick G.

Switching intermodal?

Intermodal trains don't have much switching to them.  They load the boxes on the cars in block.

Good point on the intermodal

You're right, In fact so many unit trains are just kinda boring and that is why I wanted to work a busy port and a coal branch into the overall layout. If I feel like just watching something run, the big engines with an intermodal or some other unit train. If I feel like switching, I can work at the port or the coal branch or something...

I hate tight radii but something has to give. There is just so much space. 4 axle locos to work the port and the coal branch. They will block the cars and drop them in a small yard for collection by the "around the walls" SD70s, ES44s etc.

Four axles on the branch

Like you, I wanted the interest of a coal branch.  My layout's branch line consists of 18 inch curves and 4% grades.  The six axle engines don't perform well there but the four axle engines have no problems.  With good track laying it's possible to back a string hoppers anywhere on the branch line.  Good luck with yours!