I used to not clear simulator until extended battles were introduced. When that happened, I thought the easiest way to prepare for a seven or more fleet pileup is to find ship builds that can handle the entire simulator. I have fought few battles that had more ships than the whole simulator, and simulator does not have officers, unlike campaign.
If I build ships for only one fight against another fleet that cannot have more than 25 ships, it probably is a good idea to use missiles other than Pilums. Campaign is an environment where endurance is generally more useful than total domination over a single normal-sized fleet.
Cyclone Reapers are enough against a normal battle. With Expanded Missile Racks, you generally have enough to use them as primary weapons. I used to use them as a primary weapon with Aurora when it had large missile. Only when building for those grueling simulator battles is when there are not enough torpedoes.
Heavy blaster on a brawling Conquest is good, especially if it has flak mounted in some of the ballistics. In that case, got to make up for lost firepower, and heavy blasters are good at that. Similarly, if I need a brawler Conquest to really kill quickly, I use IR pulse laser plus IPDAI. Mjolnirs and Heavy Blasters are good for Conquest if it needs to get closer to hit things with PD weapons. I would not use Heavy Blaster on a Conquest built for long-range sniping (with 1000+ range weapons).