I've glanced over other slot machine threads, and didn't come across this idea, but I think a reasonable fix for the slot machines would be to add a "sliced" slot machine coin that could be included with the reward for completing the daily/weekly missions. This could include 1x coin for each random flashpoint daily, 2x coin for each pvp daily, and 4x coin for the gsf daily. Then a few more coins for each weekly.
I think that these coins would add value back to the slot machines without creating an environment where player's can farm materials from the machines faster than players that are using crew missions to acquire materials.
I haven't done the math, and am certainly open to others' feedback but I think if the coin should give players a guaranteed chance to win one of the following materials at significantly higher rates:
50 contraband cartel slot machine coins
20 scavenged scrap
10 assorted droid parts
1 jawa junk
1 cartel certificate
1 faction specific mount
Anyway, just an idea, hopefully it's a new one!