you should experience no problems with those values. as I have pretty similar myself and I like to play online loads of different stuff. It's true they aren't the best but you got to see them both attenuation and signal to noise and they are pretty acceptable and there's nothing you can do about unless it is your adapter and/or cable.
here's mine table at this precise moment so that you can take a look
Measurements
Transmission speedUpstream7707 kbps
Downstream33023 kbps
Line attenuationUpstream20.5 dB
Downstream26.4 dB
Signal-to-noise ratioUpstream13.8 dB
Downstream10.6 dB
it's a good SNR and an excelent ATTN afaik,
Been using for almost 1 year since I've moved and don't have a lot to say except for one night I had no dsl service for some reason but it might happen.
I wouldn't bother much unless I had to, in your case enjoy for a while and see if there's something that needs attention =D.