I agree, most of the crafting feats are pretty underwhelming.
Armor slopping is good if you want to use metal armor/riot shield and keep your armor penalty low I guess, but there are also feats that actually benfit from high armor penalty. It's one of the more useful ones nevertheless.
Ballistic is pretty good very early in the game, but later on that 3 DT and 9 against fireamrs is pretty much a wasted feat.
Clothier/Skinner is not that bad as the 20% more quality is universally useful, but I don't think 7 INT is really worth it.
Disassemble is good for convenience (who wants to look for another rapid reloader/super string/scopes each time they find a marginally better frame?) but the 10% quality loss makes it a pain for items that use more than one quality-based component, like smart modules. I think it would be worth 7 INT if there was no quality loss, but right now it's arguable.
Gun Nut is just terrible, not only 15% more max damage is a very low increase in DPS, it's practically worthless for people who focus on minimal damage instead. It should be 20% to minimal/all damage instead. It's only worth it if you have 7 INT for other feats, and only on builds that are not too feat-hungry.
Mad Chemist is pretty good if one wants to use chemical pistols.
Neurology is just underwhelming, the bonus is too low.
Power Management is in my opinion the best crafting perk there is if you have electronics, since it works with energy shields. It's basically 35% more HP and you can get up to 2000+ capacity with it, who doesn't want that?
Practical Physicist is pretty good if you want to see crazy number with amplfied plasma pistol.
Weaponsmith is nice, but I don't know if 5% crit chance is really worth 7 INT.