Maybe a new block: Amplifyer or something. But instead of those effects above, it gives 1.5 of the effect of each adjacent block, counting grouping values*(like power lines and capasitor blocks). It would get it's value everytime one of it's textures was loaded or unloaded**. It would explode like warheads but would have a larger radius but less damage, to deal more damage to systems.Using warheads inside your ship to provide bonuses to adjacent blocks sounds good. Assuming the bonuses are worth the risk. As a linked system, I think the above idea of putting a bubble of them outside your ship would undoubtedly be the resulting metagame. If they only provide a bonus based on the blocks they're touching, a bubble outside your ship would provide increased armor HP (if the warheads are allowed to interact with armor blocks), and nothing else.
Consider this: a warhead placed among ship systems will produce a flat bonus to the system types it is touching, for each block it is in contact with. It will generate 50 power production, 200 power capacity, 50 shield capacity, 5 shield-per-second regeneration, or 12 thrust for each power reactor, capacitor, shield capacitor, shield recharger, or thruster adjacent to it. placing one warhead inside a ball of 6 power reactors thus gives you a bonus of 300 e/sec whereas replacing it with another reactor would only have provided 25 e/s. This is assuming you've already reached the energy softcap elsewhere and are trying to fill space with huge blocks of systems. So you are getting a huge bonus from the presence of that warhead, you're trying to stuff it with as many as possible to milk it for what its worth. But if something hits it, suddenly that bonus and the systems around it, not to mention any other warheads nearby, go boom.
Building that systems block inside a sealed advanced armor bulkhead would certainly protect everything outside of it, but still the loss of that systems block if that armor is penetrated can be called a defeat. Suddenly you've lost a large portion of power/shields/thrust/whatever in comparison to its volume. So you could build safe and low-power or risky and pray your shields never drop. Or you built that block deep enough that a clever warhead torpedo or several can't detonate the entire block.
I can see it being useful for small ships as well, where space is at a premium and power lines can't be as long in the first place. Still, quite risky.
Some base(balancing and configz shenanigans)values.
1. It would deal 10 damage over a radius of 10 blocks(so 20 wide). This would be a massive area of effect that would half kill every system block in the system. If a block was hit by two Amp hits it would be destroyed.
2. It would be stopped by any armor, to prevent them being used as peircing torpedos.
3. It wouldn't be able to be logic activated, this should be a primarily a system block, not a weapon or self district tool.
4. It would have 10 health, not 20 like other system blocks, so it would detonate it's self in chain reactions.
5. It would not Amplify other Amplifyers.
6. It would cost something equivalent to a warhead, just with a different capsule.
It would add health and armor to
*Calculated when it calculates the group bounus, it divides the total amount the group gives(say, e/sec) by the amount of blocks in the group. This would be the average power per group.
**Because you cannot simply replace one block with another one, you only need to recheck and recount it's effect when one of it's sides shows. This could massively reduce lag.