"WWII fighter pilot with 400 combat missions were exceptional." — And German.
10s in all four skills requires 114,000 XP. I'm a little under 1000 days into the campaign using minimum XP rewards and my personal character has 51,300 with eight other characters grouped between 28,200 and 28,500. I expect by the time I'm done this will have run over 3000 days with most of the missions still to come being much harder, and therefore more XP-producing. My point is that characters with all 10s should be legendary, and in past campaigns it's been far too easy to attain that level.
Note that one pilot has died and five have been released so far, while those hired have mostly come in with around 20,000, so the XP totals don't match the number actually earned. Minimum rewards is working very well for me, though I might regret it if there are several more deaths. In my three previous campaigns (each around 1600-1800 days) I've had anywhere from 4 to 8 deaths, with the number decreasing in each campaign.
I agree with you about the ammo requirements. I had to add a ton to my Shadow Hawks (which each have an Ultra-5) after they repeatedly ran dry, but so far they're the only ones that were a problem. With one ton of ammo the Black Jack has only run out once, and with two tons the LRM-20 Centurion has also only run out once.
With only one ton the 6 mg Firestarters (I call my version the Infantry Killer) run out most missions, but almost always on the last turn of the game. In the low level missions (2 1/2 skulls and under) they are absolute death machines, usually taking down 20-25 tonners with one shot from the front and up to 40 tonners with one shot from the rear. Combine that with being able to jump 6 every turn so they're very hard to hit and never having heat problems — even in Martian and Lunar environments, which I'm running into a lot — and I'm strongly tempted to not upgrade them to a Vulcan and a Phoenix Hawk as I originally planned. (That's not an issue so far, as I haven't been able to accumulate the 7 parts.)
Current mechs in force:
2 Shadow Hawks (Ultra-5, ML, SL, melee mods, Jump 5) Good all-arounders. One has 135 melee damage and the other 100 + 70 extra stability damage. Only downside is that I had to trim 40 armor off each leg to add the extra ammo.
Kintaro (SRM-12 doing 10 damage, SRM-6 doing 12 damage, Jump 5) This replaced an Infantry Killer that was destroyed, but it's NOT an upgrade. A real heat pig, even though it has my only double heat sink, it's simply unusable in adverse heat environments, though not bad in Arctic/Tundra/Jungle.
Centurion (LRM-20 doing 5 damage, 2 ML, 3 SL, jump 4) My only LRM machine, it's the one I make sure always has a multishot pilot. Very useful. I was planning to trade it in for an LRM Kintaro, but that experiment was a bust that cost me over 60 days of hangar time.
Black Jack (Ultra-2, 3 ML, Jump 4) My ancestral mech, it's been in the shop for the past 100+ days waiting to complete a rebuild after getting ripped to pieces in a convoy attack. By the time it's done I hope I'll have a Phoenix Hawk chassis ready to replace it. A very good mech (better after swapping in the Ultra for an AC-2 and an ML) which I'm going to miss when it's gone. Probably a good thing I have the opportunity to get used to not running it now.
Infantry Killer (ML+10, 5 mgs, 1 mg+5, Jump 6) As described above. Eventually this will be replaced by a 4 mg Vulcan with more MLs, but I'm not sure that will be an upgrade, though I've run them before. Doubling the range on the mgs makes them much more versatile, but losing 2 of them makes them much less effective. The extra armor and being able to stay outside of melee range of most mechs will (I hope) tip the balance in favor of this being an upgrade.
In another couple hundred days I should be adding the Argo, at which time I'll pick up the one Victor part I'm missing and use that as my new command mech. Right now I'm self-imposing that I can't keep completed chassis in storage, so every time one completes I have to immediately upgrade or sell it off. I'm hoping that pretty shortly after getting the second mech bay I'll be able to drop a Victor/Archer/War Hammer/Marauder lance.