If you like the look of wood... there are many ideas here.. http://www.woodboardsandbeams.com

A nice shuffleboard would look great here.

Start by determining what kind of additional space you need... Home office, exercise room, space for teens to hang out...

Once you look at your house and lifestyle, the use for the basement may become more apparent. Once you have that, it may be easier to figure out how to achieve it... Good luck

What kind of space do you need? If you have everything, then you can consider more fun space options such as an entertainment room, gaming room, cave, wine room, play room etc.

Have a look at our Basement Finishing Checklist http://blog.resconsolutions.com/download-your-10-step-basement-finishing-checklist/ It shows you:
What to look for in your basement before you start
How to deal with potential issues
Proper basement design strategies and tips
Material Selection – best materials to use in a basement finishing project

You have a great space there that could accommodate a small kitchenette area with sofa and comfy chairs and a nice media setup. The half bath is a bonus and you may even have room to add a shower. The possibilities are endless!