What exactly do you mean by independent design? I take it you plan on letting this ship operate alone or only with ships of its own class together? In the first case, I'd recommend you to supersize it - if you meet an enemy, it will most likely be an entire group of hostile ships and a single ship of this design will be overwhelmed. If you operate with multiple ships of this class, I'd recommend the same as the previous posters have: Splitting the ships into an offensive, a point defense and perhaps a sensor class could help you fulfill all roles with an even smaller tonnage.
Defenses:
One point of armour is very low - it's literally just the bare minimum not to fall apart in the vacuum of space. I'd up it a good five points or if it's indeed intended for self sufficient operation a good ten to fifteen points, depending on your tech level.
The shield with two levels is pretty much without effect. It literally absorbs two points of damage and then disappears. It couldn't even stop a single of your own ASMs - And the recharge would take 300 seconds, meaning one point of damage absorbed every 150 seconds. You could either leave out the shield or add some more to create an efficient barrier. With delta shield technology, I'd recommend the former.
Offenses:
I like your missile design with small and large payload designs of the same size. However, your magazine capacity is way too small (I doubt you could destroy even one alien ship with your ammo) and only four AMM tubes won't protect the ship for long. My suggestion would be to outsource the AMMs into a different design and (at least) double the magazine space, if not triple.
Furthermore, your AMM range seems pretty high - almost double the range of your R1 sensor. Similiarly, the speed looks rather low (as fast as your ASM). I don't know the hit chances of your missile design, but I'd like to voice doubt about your AMM design.
The R8 MFC isn't of much use, I think - you don't have a dedicated R8 sensor and so wouldn't have much of an advantage over the R60 MFC.
Support:
The mainteance capacity is beast. I often read people suggesting a maintenance life of 1-2 years, though I personally like to go for 3-5. I'd say 14-15 is way too much, especially considering the low magazine and fuel stockpiles. If you truly want this to operate alone, you won't need more maintenance life than you have fuel and your magazines will run dry after the first contact, I'm certain.
Also note how your design has no passive sensors. Unless you want it to be always-actives, you should add at least small thermal and/or EM sensors.
