Another vote for upgrading the preamp as the weakest link in the chain for 2-channel audio. The pre-outs are a convenience but the preamp in the AVR is meant for the amps in the AVR and won't match well with anything else. Nor is it anywhere near the quality of the DAC.
Be skeptical of the advice on tweaking/cables. Not saying it's all snake oil, but be skeptical and watch budget carefully with that stuff.
If you get a preamp or an integrated amp that has a home theater bypass, you'll be in good shape. It will pass through the front right and left signal from the AVR at 100% level so that you can use both pieces as preamps for their specific function.
Be skeptical of the advice on tweaking/cables. Not saying it's all snake oil, but be skeptical and watch budget carefully with that stuff.
If you get a preamp or an integrated amp that has a home theater bypass, you'll be in good shape. It will pass through the front right and left signal from the AVR at 100% level so that you can use both pieces as preamps for their specific function.