Measure WordPress performance on different hosts

IMHO Your attempt is pointless. On shared hosting you are not going to get consistent results as the results will depend on load generated by other sites on the server, or other sites using the DB server. even worse, the results might change after you have done the testing if new sites were added to the server.

It make more sense to compare true VPS providers, but here you probably do not need anything special for wordpress and can just use whatever are the canonical performance tests for disk access, Apache and mysql.