Highlighting colors: transparency and brightness

Using Kami and Acrobat Pro I’m feeling bad the lack of features like changing the transparency, and more colors avalible.
I mean: there are many colors, yes, but for example I can’t choose a really bright color, some thing you can do in Acrobat.

I use Kami for reading academic papers, but for the study I can’t choose this app and I go for Acrobat because this two aspects:

    1. In Adobe Acrobat you can use one color for highlighting one word and then highlight it again so the color would “double” (30% transparency x2 goes to 60%, so “double” color"). That makes the highlighting of relevant words easier.
    1. As said, transparency and colors. It’s annoying I can’t choose a very intense color to distinguise it from other color of the same tone! (like dark red from brighter red).

And… I think with that I would use Kami for studying. But for now it’s a kind of pain for me.

BTW it’s a great app!