Valeton GP-50 level with HX Stomp

I just got a Valeton GP-50 to use in the effects loop of my Stomp for a few presets. However, I notice that the overall level of the Valeton Snap Tones I use as my amp tones are rather low. For anyone who uses this method, is there a good baseline volume level you would recommend using either the Stomp FX Loop block or output block?

I'm nearly maxing out the Snap Tone volume in the Valeton, and I had to raise the Stomp FX Loop Return level to +5 dB just to barely hit -12 dB for the overall Stomp preset volume. I'm just recording and playing at home currently and not playing live. I figured I should find out the recommended settings for output volume anyway. Thanks in advance.