Decreasing WAL size effects

I am planning on setting up PITR for my application.

It does not see much traffic and it looks like the 16 MB log files
switch about every 4 hours or so during business hours.
I am also about to roll out functionality to store documents in a bytea
column. This should make the logs roll faster.

I also have to ship them off site using a T1 so setting the time to
automatically switch files will just waste bandwidth if they are still
going to be 16 MB anyway.

*1. What is the effect of recompiling and reducing the default size of
the WAL files?
2. What is the minimum suggested size?
3. If I reduce the size how will this work if I try to save a document
that is larger than the WAL size?

Any other suggestions would be most welcome.
*

Thank you for your time,

Jason Long
CEO and Chief Software Engineer
BS Physics, MS Chemical Engineering
http://www.octgsoftware.com
HJBug Founder and President
http://www.hjbug.com