I had the EasyShare on my PC, and HATED it. I used Picasa instead but HAD to use EasyShare to upload all photos. It was, on my PC, a HUGE memory hog and slowed everything down very time I opened it. I was estatic, seriously, to not have to install it on my Mac. I miss Picasa, but iPhoto is close enough. Sure, there are likely a few things that were easier with EasyShare, but sooooo not worth the program taking up all avaliable computer resources.
As the poster above said, try it for awhile. If you don't like it, delete it... and rejoice that you have that option!
I do not recall a collage option in ES, but there was one in Picasa.
MacBook Mac OS X (10.4.9) Formerly Win2000 PC