Some white papers comparing the various HA techniques

http://msdn.microsoft.com/en-us/library/ms190202(v=sql.100).aspx

http://technet.microsoft.com/library/Cc917680

Do you have standard or enterprise edition? To make the secondary databases readable with mirroring you need enterprise edition so you can snapshot the secondary.

How big are the databases, and how many is a large number?

Mirroring is easier to setup and maintain but harder to make the secondary readable. Log shipping is easier to understand but a bit more more effort to set up and failover, easier to set secondary read only though and can be done with standard edition. If you want the secondary readable without interruptions you would have to hold off restoring the logs to the secondary to pre-defined times.

These HA techniques though are much more suited to DR (scale up) than HA (scale out). Gets difficult when you want the secondaries readable.

These sounds like an 'it depends' question. You need to decide what you really want from the secondaries, DR or readability, it can be a mistake to try and make a secondary fulfill both roles.