Would definitely not start a flamewar over your suggestion. I explore a lot because that the part of the game i enjoy, well not the surveyship micromanagement but the discover new system and mine them. I dont find much fun in the war mechanism against the AI, so usually I completely turn off the AI, meaning I never use warships.  I simply like to explore and extract resources build colonies, expand population, etc. I just the way i like to play, and that require a lot of surveyeing because i never meet any ressistence and use a lot of resources very fastly.

Oh, I see, my apologies for assuming how you want to play. Your best bet is to probably follow the example of other players who build large, extremely long duration survey ships that can largely operate on their own.

Hi all, I can't remember how many years ago I last actually had a ship fire at something, and it seems that I've forgotten stuff.

I've just had a lone spoiler attack my commercial fleet based at Earth, where I had a Monitor ship and an STO based. At first nothing fired back (spoiler was in orbit so in range of everything) - but then I manually toggled enemy to hostile (who knew - it was killing ships!) and the STO engaged, but the Monitor not. What might I have forgotten to do in order to get the Monitor to fire? I attach the monitor specs, but I don't think I forgot any of the basics (weapon, FC, PP)

Denethor class Monitor      2,618 tons       106 Crew       404.6 BP       TCS 52    TH 15    EM 0
286 km/s      Armour 3-16       Shields 0-0       HTK 26      Sensors 0/0/0/0      DCR 2-7      PPV 17
Maint Life 7.12 Years     MSP 193    AFR 27%    IFR 0.4%    1YR 7    5YR 100    Max Repair 50 MSP
Commander    Control Rating 1   BRG   
Intended Deployment Time: 48 months    Morale Check Required   

Rolls Royce Hobbit II M-NPE-125T15 (1)    Power 15    Fuel Use 87.69%    Signature 15    Explosion 7%
Fuel Capacity 100,000 Litres    Range 7.8 billion km (316 days at full power)

Lockheed Kinetics Firestreak 20cm HCG V40/C3 (2x4)    Range 128,000km     TS: 2,000 km/s     Power 12-3     RM 40,000 km    ROF 20       
Lockheed Kinetics Pepperpot 10cm CDCG V40/C3 (1x4)    Range 40,000km     TS: 2,000 km/s     Power 3-3     RM 40,000 km    ROF 5       
GE Narrowbeam BFC-AM R64-TS6000 (1)     Max Range: 64,000 km   TS: 6,000 km/s    ECCM-0     84 69 53 38 22 6 0 0 0 0
Marconi Spark BFC-LR R128-TS2000 (1)     Max Range: 128,000 km   TS: 2,000 km/s    ECCM-0     46 42 38 34 30 27 23 19 15 11
Hitachi Power PBR R5 (2)     Total Power Output 10    Exp 5%

GE Broadbeam  AS18-R100 (1)     GPS 1000     Range 18.5m km    Resolution 100
Ferranti  AS41-R100 (1)     GPS 5000     Range 41.4m km    Resolution 100

This design is classed as a Military Vessel for maintenance purposes
This design is classed as a Warship for auto-assignment purposes

I'm not fully at ease, gameplay-wise, with using small civilian ships with infinite autonomy; it feels abusive. It's acceptable if it's a freighter of 40,000 tons—you can imagine complete recycling of resources and enough spare parts—but here... IDK!

I have the same feeling... I think it is to some degree against the spirit of the game. But... it is up to each and everyone to decide how their world works and it does not interfere someone else's game anyway.

I just use buoy as that is what they are made for rather than using manned stations for such tasks. You can have explorers equipped with a large missile launchers and some buoys and deploy them as you explore or as part of your patrol vessels.

I use 500-ton Pinnace that deploys at the jump point. 10 years of deployment time and some amenities for the crew.

I just deploy a station with a single thermal sensor.
Since it is a commercial ship, the deploy time is moot and nothing ever breaks.
I use small commercial tugs to deploy them at each jump point as I discover them.

Most of the cost of a jump point sensor is going to be the cost of running a ship to place it, and the time spent by the player doing so.  Since you just need to be able to detect a ship making transit, if the sensors are close enough they do not need to be very big.  I suppose at high tech you have to worry about stealthed ships jumping as far from the jump point as they can, but most of the time, the detection a jump point sensor is going to give is the notice of their destruction.