Yes it is. Download dreamboard. Then the dreamboard theme. These themes are only around 14-20mb. Better than the 50-70mb themes.
After you download dreamboard, click on the icon and you will see your themes you downloaded. Make sure you download specifically dreamboard themes. They have their own section in Cydia.
When you open dreamboard they have a android default theme. Do not enable the widgets in that theme. It will lock your phone up.
But overall simple to use. I left my original theme enabled in winterboard. So my dialer and misc stuff is still using winterboard theme behind dreamboard theme. Hope that made sense?