Speaker Recommendations $2-4k a pair used

I have set up a two-channel system around my 16 year old Thorens TD 320 MKII turntable (with Shure VST III cartridge) that I recently brought out of storage. I purchased a dealer demo Parasound Halo P3 preamplifier and Parasound Halo A1 amplifier from eBay and Audiogon respectively. I am utilizing a set of Paradigm Reference Studio/40 v.2 speakers that I purchased new 7 years ago. These speakers were in my home theater but were replaced there by a pair of Studio/20 v.3's when they did not fit our new family room's built in cabinets. They are on matching sand filled Premier stands. I also purchased new bettercables.com XLR interconnects and speaker wires.

I love the sound of the Studio/40's; they were purchased as a compromise when I could not afford Studio/60's 7 years ago. The only thing I think they are lacking is bottom end, and that not too often. I listen to all types of music - some of my current favorites are Kate Bush Hounds of Love, Indigo Girls self titled, Supertramp Crime of the Century and Allison Krauss and Union Station Live. I also like Metallica, Creed, Pink Floyd and 70's rock bands like Boston, Journey, Styx and REO Speedwagon.

I am looking to replace the Studio/40's with a larger speaker with better bottom end. I am considering Paradigm reference Studio/60's and Studio/100's but would like to consider others. I'm looking for recommendations of other speakers I should consider...