Note Transportation Options
The Archeologia has no transportation.
Yet, you could just add a Transportation Pass.
Depends. I loved being able to use the Subways and the Buses unlimited for the duration of the Roma Pass Card. The Plus PIU, which is new to me, even gives you access to regional trains. There is rarely a line for Ostia Antica; the Forum or the Palatine Hill. The Roma Card is used mainly to bypass the Colosseum Lines which are always long.
Since you are in Rome for four days, adding the Acheologia Card seems excessive and slightly redundant. The Roma Pass will cover the train to Ostia Antica - Lido - and back.
How you time the start of the card is something to consider. It counts the remainder of the first day you use it, till midnight, as its First Full Day even if you start the card at 18:00. Buying the card doesn't start the clock. The clock starts, and gets an electronic time stamp, the first time you use it for an entrance.
Oddly, information on other blog sites seem to be saying that the Express Train from Termini to Fiumicino Airport isn't covered by any Pass Card. This is frankly weird.
So,..... I have a question now.
Has anyone used the Roma Pass Plus to take a Contral Bus or the Slow Local Train, FR1, from Roma Ostiense to the Airport by using the last day of the Roma PIU Pass?