I've always been a fan of Yamaha amps (updating to DTS is worthwhile) and Richter speakers. I have found both tend to be good value for money. My fronts are Richter Wizards - 15 years old, still going strong, sound good and I have no intention of changing them this side of a Lotto win.
The thing with speakers is they are a very personal choice. It's what YOU like that's important, just because I think brand A sound too tinny or lfeless, doesn't mean you won't love them. I would recommend you at least audition the Richters if you decide to purchase new speakers.
BTW, if you are going 5.1 surround, it's often best to make sure the fronts and centre are the same brand so the sound doesn't change "colour" as it moves across the sound stage. This also applies to a lesser extent to the rears. Subs are not as prone to this.