It would not be a great FA period for the Cowboys, but it certainly wouldn't be bad. Frankly, if one were honest, it's probably the best they could have done given the limitations they put on themselves in FA.
Make no mistake, a guy like Iloka isn't a solution. He's a short term fix. The Cowboys can still draft a S that they like if the opportunity presents itself.
There is no way the Cowboys would do this, but I'd still sniff around Suh. The market for him seems light right now so I would guess he's trending towards signing another one year deal. Suh, again, is not a long term solution. He's no longer "elite". But he would present an upgrade on what you have.
If the Cowboys brought in Quinn and Suh, suddenly the DL is looking pretty darn strong:
DE - Lawrence, Taco
1T - Suh, Woods, Covington (can probably swing between 1T and 3T)
3T - Crawford, Collins
DE - Quinn, Armstrong, Gregory
Draft either a 1T or a 3T (or both) and suddenly that DL is looking like a strength of the team.
PS - If Suh turns you off, then I'd still look at a guy like Shelton to plug in at the 1T. He provies little in the passing game but is an active run stuffer.
PPS - Sorry for the typo in the title!