Very nice, neat and clean setup!
Suggestion ko lang -- before upgrading your speakers, I suggest you upgrade subwoofer and then AVR.
Kung kulang ang bass, the subwoofer might be sufficient. Just make sure your speakers aren't set to "Full-range" or "Large".
You should get an AVR with Audyssey MultEQ or MultEQ XT, not just 2EQ. There's a huge difference, especially for the bass frequencies. That will again improve your bass.