Best way to improve my Theater with $1500.00

Do nothing until after you move. Once you are in your new home, access your needs then. If you are like most people when you move into new digs, there will be many, many more needs for the $1,500.

I'm about 100% certain that all of your guests will mostly be WOWED by a huge HD front projection screen image, over any upgrade you could make to your audio system!
There's simply no replacement for the immersive impact that a large screen experience offers!
If it's me, I'd ditch the 60", and you can get STUNNING huge screen, ulta high quality imagery, going JVC projector, from any of the following - HD350/RS10/RS250/RS15/RS20/RS25/HD750/HD550/HD950/X3/X30/RS40/RS45/RS35.
ALL OF THE ABOVE ARE CAPABLE OF DARN NEAR WORLD CLASS 1080P IMMAGES OFF A STANDARD WHITE - even cheapo - projection screen! (dark room, necessitated, in any case though - uness you got light rejection screen for bigger budget).
I dare you to get more "WOW" out of your system than upgrading to quality front projection!
That's just my thoughts .. but then I have been in and out of high end audio/video for 18 years. Now, sound isn't a huge priority, as is video. But that's me.
If sound is going to be most important for you right now, you're going to find you get most upgrade from speakers!
Better, more effective home theater speakers are going to have the most dramatic improvement in sound for you, yes.
You'll spend more on higher end music capable speakers, that also do super dynamic, coherent, transparent, effective HT speakers, but they're out there.
Look through your Stereophile and Ultimate Home Theater, even HT magazine recommended components and reviews for high end speakers that double for HT duties, effectively, and that should help.
Sure,..stay with your B&K (I'd upgrade if no current HD codecs or HDMI switching though), and focus on loudspeakers for audio, yes. If you must do full range loudspeakers for 2 channel, etc, then look into ultra high efficiency, Dappolito, multi-woofer/tweeter designs for strongly reinforced sound propegation, and solid soundstage, speed of and impact of mid/hi freq sound, with good focus (especailly vertically) and coherence. Powered woofers help GEATLY for dynamics, and horns always have lots of pressence, and focus, and strong dynamics and efficiency. So consider.
I would stay away from more delicate, open, single mid-woof/tweeter traditional stereo speakers for all out dedicated movie speakers. You'll find they're the opposite of what a good dynamic, hard hitting movie theater loudspeaker - with lots of presence (not laid back) - has to offer! So choose wisely.
Yep, first front pj upgrade, then consider maybe high end dedicated movie monitors, and mate quality subwoofers with em!
There's a ton of monitor system upgrades you could have, USED, for $1500 invest, sure!
Hope this helps

I know that I will need to spend money on a good projector. I will make the room with no windows. So light isn't an issue. I also know I will spend thousands of more dollars. Just anxious to buy something now. Hahaha.

My speakers already sound darn good. Won't I have to invest tons more money to get better sound out of my speakers?

I appreciate both of your suggestions. I am looking for as many opinions as possible to make an educated decision.