For light reading, and especially for reading in bed, I've learned to read on a tablet. I like being able to prop the thing up, not having to bother about holding it or keeping the pages from flipping around, and being able to "turn the page" with the flick of a finger. As another one with aging eyes, I also appreciate being able to adjust the text size. I almost never buy e-books -- my local library has an excellent selection of downloadable books, and there's also the
Open Library, through which one can have access to almost anything.
But for serious reading I do prefer "physical books." If it's non-fiction, I want to be able to flip back to find an earlier reference to something, look at the end notes, find things in the index, etc., etc. All that is just too messy with e-books. And for serious fiction I just need paper, and to hold the book in my hands.
There's a free library program out there called Calibre, which is great for organizing an ebook collection and also lets you convert from one ebook format to another, e.g., from Kindle format to epub, or vice versa, and allows you to format the text according to your own preferences: there are many more changes possible than just altering the text size. I highly recommend it. I run it on my laptop, and it's very easy to sync it over a wireless network with other devices.