...jumping jack (-3 to hit).
-2, actually. -1 in Alpha Strike.
A lot of this feedback that is being given will largely depend on how it is implemented, I think.
For example, Jumping Jack can be quite powerful when considered in an open environment that someone can get for effectively free, either as part of a Formation bonus or just playing with pilot cards. However, when considered within the auspices of Campaign Operations, if a pilot needs to earn this ability through experience, and is the same cost as just improving a Pilot's Gunnery by 2 (unless there's a campaign rule limiting difference between Gunnery and Piloting), it's perfectly balanced within that context.
With that said, and with the caveat that I'm proceeding on the Campaign Operations method of purchasing these Abilities as I mentioned above, on with the review:
Forward Observer - Campaign Operations - Rating: OP but SituationalFor the cost of improving Gunnery by 1, you can effectively improve your Artillery's Gunnery by 1, 2 if you shoot. The only reason it is situational is that Artillery is not always available. Alpha Strike is less situational because it works as a free non-shooting TAG for non-Homing IDF. It's a good price for Classic, but too cheap for Alpha Strike.
Heavy Lifter - Campaign Operations - Rating: Almost uselessLifting more weight is great if you need to grab something, but usually most scenarios don't call for carrying something that a Spider can't Lift normally. It might be fun for grabbing a Savannah Master or APC to throw it off a cliff, but otherwise useless in most gameplay.
Hopper - Campaign Operations - Rating: Good, sort ofWith all the Legs that get lost in a game, being able to stay Standing is very useful. However, unless this is assigned for free, I don't see a lot of players actually getting it, as it costs the same as another Lucky, Float Like a Butterfly, or Inspiring Commander.
Human TRO - Campaign Operations - Rating: Too Good, maybe?Okay, this is an odd one. In Alpha Strike, this is almost useless. While forcing a Crit is very good, you only get to do it once per game. In Classic, it is godly. Being able to get a Determined Crit with an average roll (which is about 50% of my denied Crit Rolls) can be huge. We have a player who has put it on all his pilots, and his pilots become killers with this. It's also cheap as chips, but because it only affects a die roll by one, I'm hesitant to advocate for this being more expensive.
Iron Will - Campaign Operations - Rating: Way too SituationalMuch like Hopper, it's a good thing this is cheap. Unlike Hopper, I've lost far more Legs than ran in to users of Morale Attacks. If those Morale Attacks were more cost-effective, and thus more likely to run in to, than this would be more worth it.
Melee Specialist - Campaign Operations - Rating: Very GoodStronger in Classic than in Alpha Strike. Being able to Hit more easily with Physical Attacks can make the difference in a lot of situations. However, being able to do just that much more Damage can be tremendous. In our local biweekly campaign, this is a favorite and first step for our pugilist pilots.
Oblique Attacker - Campaign Operations - Rating: Under-costedIt costs the same as improving Gunnery by 1, removes the base cost of Indirect Fire as well as the cost of a Spotter. In Alpha Strike is a bit more balanced in that going without the Spotter actually changes the cost of IDF to make it harder to do. It might be wise to have 2 levels of this ability, the lower cost one has Alpha Strike's no-spotter penalty, while the more costly one removes the Spotter penalty.
Slugger - Campaign Operations - Rating: SituationalIt's a good thing this is cheap, because it is so situational that I can't see this being deliberately taken. Anyone who would want to take this would either get a 'Mech with a Hatchet, or customize their 'Mech to have a Hatchet, and save the cost for something else. If SPAs are being randomly assigned, it's useful, but the Club rules are so useless we often ignore them in our interactions and go for Kicks.
Stand-Aside - Campaign Operations - Rating: Very SituationalThere are few times I need to bypass an enemy unit through a hex they are standing in. In those times, it's often more useful (and fun) to use a Push, Charge, or DFA to Displace them, or just simply Jump over them.
Animal Mimicry - Campaign Operations - Rating: Very SituationalThere are two costs to this SPA. First is the cost to buy it, and the second is they need to be piloting a Quad. If you have a Quad nut in the party it is VERY useful, but for a Biped pilot it's pretty much useless unless your opponent/GM is a very nice guy. That it blends well with Demoralizer isn't much a help because of Demoralizer's faults.
Blood Stalker - Campaign Operations - Rating: OvercostedThe cost is twice what it would be to improve Gunnery by the bonus you get. Add in the fact that there is a penalty against non-Prey AND it only works once in a game, and it pretty much becomes contra-indicated to purchase in Classic. Alpha Strike is still overcosted, but you can use it more than once in a game.
Cluster Hitter - Campaign Operations - Rating: Meh.Being able to do Aimed Shots with Cluster Weapons, and without a Targeting Computer is awesome. That it is not tied to a specific weapon like Sandblaster helps things out. Only being able to use it one only one weapon at a time sucks, but understandable. Having to Stand Still sucks even more and is punishing. Good for mechs carrying a single Cluster weapon like a HAG, Rotary, or the Thunderbolt's LRM-15, but not really a strong contender when Sandblaster, while more restricted in variety, offers more overall Damage and works with IDF.
Dodge - Campaign Operations - Rating: OddI agree with others that the rules could be written better. That being said, it's great if the pilot gets in to Melee a lot. In our campaign we dealt with a Dragon with this ability, and the only thing that prevented it from being more annoying was when I shot it in the back and nailed its Gyro. I can't say its not worth getting, but most of our melee pilots prefer the offense over the defense at present.
Eagle's Eyes - Campaign Operations - Rating: SituationalHaving increase Probe range is good, if there is anything to use the Probe with. Most scenarios don't have traps, Mines, or Hidden units where Probes are useful. Honestly, every time I think of this, I keep thinking it costs less than what it is, and that's probably due to its situational nature.
More to come. This is long enough as it is.