In short, you're using a 7" as I use my 13" laptop. It strains my eyesight to use a 10" as my laptop. I assume this is an age thing; I'm over 40. It influences the eyes badly, sigh.
The nice thing about the 7" is that I can hold it in one hand close to my eyes when sitting back or lying down (it's more comfortable than I can make it sound). It works without my contacts in, which is my yardstick for good enough. I'm sure my eyes don't love me for the close work, but my back wouldn't love awkwardly using a laptop more, so it's all a tradeoff.
In short, you're using a 7" as I use my 13" laptop. It strains my eyesight to use a 10" as my laptop. I assume this is an age thing; I'm over 40. It influences the eyes badly, sigh.