hoplites? medium infantry?

Am I missing something here? Do the hoplight units supercede the MI in the exp 1 scenarios? and on what occasion would you field Hoplights with other medium infantry? I dont have number six yet but hope to grab it up in a couple of weeks. Did we get redundancy regarding mediums vs hoplights? I understand the rule difference regarding the order horse/mounted units but whydo we now have different blocks for MI and Hops? I confused. (I am more 'read' on the Roman eras than Greek ones)

Exp 6 has redone some of the scenarios to replace MI, and some HI as well, with MI hoplites. Some scenarios such as Marathon have not had an upgrade but I suspect we will see this in the future (C3i?). The successor battles have not had any hoplites and they remain unchanged apart from giving options to use some of the new coloured blocks such as the Silver Shields.

So basically you will only use hoplites when a specific scenario gives specific instructions to do so.