That is interesting. I also am running gsoil (1.6.7) on linux compiled from source using go (1.8.3).
i downloaded the windows SOILSafe wallet and used it to make the transactions, also first try was with the default fee, this didn't go through, so i increased the fee some more and that went through!
I am not having any luck with the windows client and the SOILsafe wallet either. Transactions seem to send but they never reach the blockchain....