I also generally tier my ships by the number of size 50 engines they use, to get the best fuel efficiency, so my ships are generally 7500/15000/22500/30000 tons (and so on; 1/3rd engine each).
Yeah. For my old design I was using size 50 engines with about 0.75x power. I've been reworking a few overnight designs and god-- you guys are a lifesaver. instead of my nearly 40kton--jack of all trades, master of none ship I've shaved off about 30ktons.
that means? Everything is faster. Everything can fit more weapons per ton and still be faster. I can either fit in a slow, heavy engine for enhanced fuel efficiency or a fast, smaller engine that burns a bit higher. At least I can use the slower, big engines on my missile frigates (circa 10kt craft) In all cases my speed is back up to above 3k km/s minimum, and my new generation of FACs are topping about 4-5k. Obviously that means any ship I make will be at least able to dodge missiles slightly.
Also, someone said about low tiers having terrible efficiency ratings-- you're right. I really wanted one of those 5 cargo hold freighters, but dear lord the speed would have been pitiful. So I designed a 2 hold one, which has been a lifesaver. it's slower than my old 1 hold design, but it's so much simpler to set up automated mining colonies. Next I need a supply ship for combat duties-- I'm thinking about a jump-capable Tanker/Collier/Maintenance vessel, with some decent sensors. I might even make it a carrier. Ideally it would hang at the jump point with a small area-defence force while my frigates and cruisers move out. If it ends up being ridiculously huge I'll go back to individual vessels though, since my current tankers are pretty damn efficient at the moment.
2-hold Freighter. I could cut the fuel in half, but there are some juicy comets on the out system.
Sirius class Freighter 64,600 tons 165 Crew 824.2 BP TCS 1292 TH 1500 EM 0
1160 km/s Armour 1-143 Shields 0-0 Sensors 1/1/0/0 Damage Control Rating 1 PPV 0
MSP 8 Max Repair 75 MSP
Intended Deployment Time: 12 months Spare Berths 0
Cargo 50000 Cargo Handling Multiplier 20
300 EP Commercial Ion Drive (5) Power 300 Fuel Use 5.3% Signature 300 Exp 5%
Fuel Capacity 500,000 Litres Range 26.3 billion km (262 days at full power)
This design is classed as a Commercial Vessel for maintenance purposes
Edit: Also, probably the most important thing I've learned is missile defence. I was thinking that with a 90kkm laser I could get 2 or 3 shots on something like a 15000 or 20000km/s missile. Then I remembered the smallest increment is
5s. /facepalm. Yeah, I'm redesigning my Missile sensors now
The old kirov design would be able to attempt to intercept three missiles
once per 5s. With four turrets. Granted, those first three missiles (assuming they're 20kkm/s) would probably get shot down and MAYBE another one to the CIWS... But dear lord if I was building a 10kt dedicated missile frigate these things would get
creamed.