Whether you should use it depends on what kind of battle you're in and how you play. If you don't mind using mostly fighters in Blitzkrieg, the F4F is the way to go. What I primarily did with the F4F on the Bogue and Independance in Blitz was use it in masses - launch 6 or 7 at a time, and have them patrol the battlefield searching for enemy fighters and bombers. You will not have any competition outside of KM fighters and locals, and even then, you are probably still better than the KM fighters, and just fly out of the locals' range and wait for them to either return to the carrier or run out of gas and crash. Using F4F's in this way is much like the way you will use higher tier fighters in Great Battle.
On the other hand, if you prefer bombing in Blitzkrieg, I recommend you do this: You keep 2 P-55 Ascenders fueled up on the deck at all times, and continuously launch bomber waves in the meantime. If danger approaches (3 or more planes flying in a group) launch the P-55's and rip them to pieces. Two P-55's (referred to as "locals" due to their fuel amount, forcing them to remain locally near the carrier) will ALWAYS be enough to deal with 6 or 7 bombers/tier 1 fighters like the F4F. Only carry about 4 P-55's as they take up extra deck space, and in blitz you only need maybe 4 or 5 at the most. It all depends on what kind of CV player you are.
In Great Battle, during the lower levels, I highly recommend carrying P-55's because they can deal with mid tier fighters. I haven't played with locals against the new tier 4 fighters (F8F Bearcat, He-100, Blackburn Firebrand) but they will eat up most mid-tier fighters. They are also effective at downing bombers. They are fast and have high firepower, so to make up for their lack of range travel near the BB's (not in the middle of them, but just behind them, closer than a bigger CV) and be very watchful. It's good to develop CV situational awareness, because in some maps you can cross people, get stranded on the other side of the BB line and shot to pieces, and even sail off the map and be dismissed from the battle if you don't pay attention to where the carrier is going.
Stay with the P-55 until about level 70. For me, I had an Enterprise Event Carrier, so I used the P-55's until I began using the Enterprise, when I switched to the F6F. By this time your fighters will have enough ability to give most other nations' T3's and all bombers a tough fight, so now you equip the F6F Hellcat. If the nation has notoriously bad fighters, you may even be able to destroy the T4's at this state, if your pilots are good (mine were EBVE, and did). And when you hit T3's, the F4U Corsair, get ready for some fun!
