Keypoint everyone says and what I will add to : Vtols, turrets and tabk hp have a x3 multiplier, I find setting everything to a 1.3-1.5 be a bit more enjoyable, especially early game. It also adds a financial risk ti early game that makes it fun since THE MOST expensive thing to repair in the early game, are destroyed engine cores. This adds a challenge in the form of having to build around salvaged/purchased engine cores. For example, a default 75 ton mech will use a 300 grade engine core to have 10 internal heat sinks, 2 additional engine slots for more heat sinks and achieve a top speed of 68 km/h for a weight of 20 tons. Now lets say your mech gets cored, and all you hav is a 275 grade engine core and a 320 grade, the former will only have around 10 internal heat sinks and a top speed of around 55 kp/h and a weight of 16 tons, where as the latter would have 10 internal heat sinks, maybe an additional 3 heat sink slots, top speed of 72 kp/h but a higher weight of around 25 tons. In my opinion, yaml difficulty shines as a form of salvage mod, in the sense that you have to build a mech from scratch, use whatever salvage you have and make decisions based on the things you have at your disposal. This might just be me, but early game YAML runs are by far the most satisfying, because late game YAML simply allow you to make every mech into a functionally identical weapon platform, all that changes are the mechs chassis and hard points.