Paris pass vs museum pass

the Paris Pass is a tourist rip that just buys up an ordinary museum pass and an ordinary Paris Visite transport pass and a few coupons, puts them in an envelop and charges gobs more for them than they cost separately. The Paris Visite is a tourist rip off product and almost never a good choice for a transport pass. If you are there in a week roughly Mon-Sunday then get a Navigo Decouverte; if your week slops over two weeks, then just buy carnet of 10 ordinary metro/bus tickets for 14.10 and buy another if you run out. If you do day trips out of town e.g. Versailles or Fountainbleau or whatever then buy specific point to point tickets for those trips (and get two each -- one to and one from)

The Museum Pass is probably a good idea for a first trip and a 6 day pass is cheaper per day if you are going to be visiting many museums and monuments on the pass. At some venues you get to use a shorter security line e.g. d'Orsay, Orangerie, the Richelieu entrance at the Louvre. At other sites you stand in the same security line but can skip the tickets lines in side e.g. Ste. Chapelle and Versailles. It also allows multiple visits; for us two or 3 three hour visits to the Louvre are much better than a full day to get our money's worth. You can also visit places briefly that you might otherwise skip if you had to buy a full ticket. Just buy it at the first place you visit and make that a less heavily visited place e.g. maybe the Cluny.

If you want a Seine cruise or HOHO bus or whatever just buy them on the spot; no need to plan those. And if you have an expensive Paris Visite in your Paris Pass kit then the HOHO is going to be a tad useless and vice versa -- you can't do everything at once.