Goal-line tech is immaterial. What's needed is good-quality refereeing. Technology would be useful for the edge-cases, when it is uncertain whether the call has crossed the line, or if the attacking player was within a foot of being on-side. Neither of these cases, nor Thierry Henry's blatant hand-ball in the qualifiers, should be a matter for the beeping machines.
I don't know much about football, particularly not the org structures of referees, but that appears to be what needs improving. Seems to me that a 3-challenge video-replay system would help deal with the most egregious cases with technology that's available to all the major leagues already.