Pina, based on your priorities, I think the iPad would be a good fit for you. I have both a Kindle and an iPad, and for reading, I much prefer the Kindle (much easier on my eyes). However, the iPad does have the advantages that you mentioned (more readable formats due to access to different apps, color for comics, magazines, etc).
I'm a heavy ebook reader, however, and if I had to choose one, it would be the Kindle. But I'm not you.
