With Eck being an R1 and being set to not use before the 8th or 9th inning, someone else is gonna have to get those innings, it's inevitable. Especially in a $100 mill league with a DH, you're gonna have some of those high scoring games and you're gonna get into your pen quicker than you'd hope.
FWIW, I like the team, though I think platooning Horton with Walling might be overkill. Horton would probably do fine on his own. Either way the defense is gonna hurt you.
One other thought is that Wagner is great, but if you're not gonna play him at SS, why not just get a Patsy Daugherty type to play DH for less money and less injuries?
Other options to consider in LF or DH are Cleon Jones, Joe Medwick, Joe Evans, Bing Miller.
If it were my team, I'd play Honus at SS, drop Fernandez, DH Horton, drop Walling and then pick up a solid LF with the leftover cash of roughly $7.00 Mill ....... If you did it right, you'd have the cash available to improve your pen.
Just my $0.02 worth. Hope it helped, or at least didn't screw you up too much.