I think the easiest thing to consider is that Klipsch is known to fudge some of their spec. Specifically the sensitivity. IIRC, Shady's review just a sew weeks back tested out at 92dB instead of the reported 96 or 97dB. Not shabby... no reason to lie about it!
They've been labeled as sounding great for Rock and HT, but not much else... Again Shady's review was pretty good. Perhaps they color the sound a bit because of their brightness. My understanding is that Klipsch modified their tweeters to be less bright and to blend better, and it seems to show in the newer gear.
So its not really, now, that "Klipsch is just bad," its that they are doing some things right.
For myself, being into critical Music listening with a hint of HT thrown in, I know Klipsch aren't for me. Our friend Danzilla LOVES his new Klipsch rig. And its all good!
I think for yourself... and really anybody that is considering a change to their system, you have to start by defining your goals: What do you want your rig to be? Music or HT? If any music... do you listen Critically, or passive? (Is MUSIC what makes the world turn for you, or is it just aural decoration?
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Then consider how big your room is? Your listening habits? How far do you sit from your speakers and how loud do you want to listen? How much are you willing to spend?
Anyway... If you want to improve Sound Quality, then you replace speakers. If you like your speakers and you want them to play louder, you buy a good amp that will power them appropriately. If you want to have the latest connectivity and video capabilities, you buy an AVR or Pre-Pro that matches your needs.
If you've got most dialed in, but you feel you lacking something down low... then subs are where you look. Unlike above, room volume is more important for subs rather than distance from.
Regardless, if you like your speakers, then be happy with them. If you think you want something more out of your audio experience, then consider changing up.
If you haven't heard accurate speakers, go find some to listen to. Just to have the experience.
Cheers!