craftgrrl | Altered book sealing question?

Hello again, ladies!

I'm working on another altered book project, currently. This one is for the same friend as the last one I did, but its a collaboration this time between myself and my best friend, for our mutual friend.

I started with a children's "board book." These are lovely to work with - the pages don't curl all to hell. Yay! :D Its a short little thing, made to illustrate the song "La Bikina," a Mexican folk song that this girl absolutely loves.

I've done two pages, so far, and the covers.

The cover is covered with felt, and at the center is a printout of my painting, La Bikina, seen here. Here's the cover:

Here's the first page spread I did:

This part comes at the beginning of the song

And then here's the other page spread I did, at the back of the book/end of the song:

(On the pages, the big open blank spaces you see will eventually be filled with drawings by my friend, when I send it to him to finish up)

The materials used inside the book are:

Acrylic craft paint
Cut paper
Elmers Glue
Confetti (paper and plastic)
Fake tattoo
Stickers
Ink jet printed things (on paper, of course)
Photocopies (the words - toner) transferred onto the pages with a Prisma blending marker
Torn book pages (older paper)

My question is: Considering the things I've used on the pages, would it hurt the pages to seal them with Mod Podge? I don't have anything else that I could use as a sealant... I just want it to all stay in place forever, and also I want to kinda unify everything. But I'm worried that it might make the inks/toners run/bleed, ruin the tattoo, and/or make the pages stick together, should the book be closed for a long while (on a shelf or something, once we give it to her.) Am I worrying for nothing? Should I just go ahead and use the Mod Podge on it? Is there something better I could probably use? Any help is appreciated - Thanks!! :D