Update from my time with the Merchant Marines mod - plus details for anyone interested in the general combat system.
Chatted with the dev for a while. The most important detail is the mod gives small engines a multiplier on Agility and Speed dice. The bonus is specific to three smaller engine types: mass 2400s engine x 2 (aprox +27 dice); mass 3400 engines x 1.5 (aprox +12 dice); and mass 5000 engines x 1.25 (aprox +5 dice). Larger engines are not modified.
Per the normal dice and combat pool rules, these are Strong dice, which will succeed 40% of the time. So a +12 dice bonus on a 3400 size engine would be +4.8 successes, on average.
You can see all of this in the ship combat screen when you hover over the ship. It will show your combat pools (eg Accuracy), and what they are made up of (eg Speed and Navigation), and what the totals are. You will NOT see the engine size modifier, its built into the engine Speed and Agility rating. When your 3400 size engine says 36 Speed and 36 Agility, that already includes the x 1.5 multiplier which brought it from 24 base +12 bonus = 36.
This does not scale with difficulty level. I play on Demanding (5/8) and the dev plays on Impossible (8/8). Some of that is why I found ship combat a little easy.
However, most of the reason I found it easy was because of my own Officer choices, and some lucky bonuses to their Tactics skills, plus the variability of enemy ships. Sure, there is a +12 bonus from the engine, but I also had a +17 bonus to Tactics from lucky Officer traits. When I was fighting enemies less than my level that means I was hitting a lot.
After commander level 20 its starting to even out. Sure I hit a lot, but I am also getting hit back. I think its going to keep getting harder.
So the result is I think the mod is balanced well.
My commander is up to level 23 now. I added a third class to most of my Officers. I stopped taking main quests, and am now taking random quests from other contacts.
I still prefer this “10 Officer” style of play. Let’s see how far I can get!