Not enough bandwidth for a guard as far as i can tell.
That's my thought as well. Quoting Roger from a recent thread (from here: https://lists.torproject.org/pipermail/tor-relays/2016-December/011519.html):
"You need to get in the top 25% of the relays by speed. "Speed" in this case refers to consensus weights for recent enough authorities, or the number advertised in your relay descriptor for older authorities. Right now that varies by authority but it's in the 4 million to 7 million range."
But, no worries, I think your relay will still be useful as a fast middle node in an under-represented region. Thanks for running a relay!