What other acids could be used?

propanoic acid, xxxx xxx and xxx could be used.

Can data loggers be used?

Yes, data loggers will work but you have to think what you want to get out of the activity. For example, using a data logger with this activity as part of a class demonstration may allow you to enhance your commentary of what is happening. However, you may wish to do this as a class exercise, allowing students to take readings manually, to practise their practical skills, plotting and interpretation of results.

Will this work the other way round, for a base being titrated against an acid?

Yes, you can apply the same procedure and manipulation of results, for example, determining the Ka of the conjugate acid produced during the titration.