Additions / Tweaks?

Hi

Really like the Arke theme but was wondering if it’s possible to add:

1.) A searchbox or “spyglass” to the main menu. I like this option where you have it on your other themes.

2.) An “older posts” “newer posts” link at the bottom of the blog roll.

3.) Is it possible to add a little more space between each post? When one ends and the title of the next post begins?

I don’t think these would disrupt the minimal look.

Thanks for any help.