Whoever told you its not powerful enough is full of it. Those are 90dB speakers. They will be just fine with as little as 20 watts. Your receiver has a lot more than that.
Power however is one thing. Quality is another matter altogether. Your speakers will sound a whole lot better with a good 20 watt stereo amp than they ever will with any AVR.
Quality also is a lot more than speakers and amp. Interconnects and speaker cables make a big difference as well.
Before looking around you need to decide what exactly it is that you want. If you want all those channels then you are doing just fine. Your AVR has all the power and channels you will ever need. If you want quality though then you will want to look elsewhere. No AVR ever made has good sound quality. So it all depends on what it is that you want.
Power however is one thing. Quality is another matter altogether. Your speakers will sound a whole lot better with a good 20 watt stereo amp than they ever will with any AVR.
Quality also is a lot more than speakers and amp. Interconnects and speaker cables make a big difference as well.
Before looking around you need to decide what exactly it is that you want. If you want all those channels then you are doing just fine. Your AVR has all the power and channels you will ever need. If you want quality though then you will want to look elsewhere. No AVR ever made has good sound quality. So it all depends on what it is that you want.