This is the same issue seen with the abiword package. goffice claims X.org 7.1 as a dependency so you can't install gnumeric into VL 5.8 SOHO without the --no-dep option. Once again I think it's an error in the slack-required file rather than a real dependency.
I do have a newer goffice package built against a clean machine (no X 7.x, no GNOME) so I will offer that in the appropriate forum. Just an FYI...
eMachines EL-1300G desktop, 1.6GHz AMD Athlon 2650e CPU, 4GB RAM, nVidia GeForce 6150 SE video
CentOS 6.5 (will try VL64-7.1 soon)
Toshiba Satellite A135-S4727, Intel Pentium T2080 / 1.73 GHz, 2GB RAM, Intel GMA 950
HP Mini 110 netbook, 1.6GHz Intel Atom CPU, 2GB RAM, Intel 950 video, VL 7.1