good advice. Flash helps. You may want to increase your flash training. Also, you can get rid of the c4 with a missile, bombing run, or paratroopers; or use gordos which can take a lot of damage. What is your typical troop mix?
I don't have a mix, I use all flacos. My flashbang is already maxed out for my level, as well as missiles, firebombs, flacos, all 4 squad camps and helipad. I use 3 diegos and 1 scorpion with a total of:
+126% missile damage
+38% firebomb damage
+40% flashbang duration
+15% energy gain
I'm not sure using gordos would help a lot in my position since my gordos are level 9 and my flacos level 16. Here's a quick comparison:
Using flacos:
total troop health = 124,992
total troop damage = 28;224
Using gordos:
total troop health = 144,256
total troop damage = 3,296
As you can see the health is barely superior for gordos (and the risk is concentrated on a lot smaller number of troops), while the damage is almost 10 times superior with flacos.