What other traits do you guys find too strong or too weak?
I'd add the one that increases ship repair rate as a very weak trait, not because it is weak in and of itself but because strategic repair is just garbage in GCIII. Who cares if I can get a +15% or +25% strategic repair bonus to add to my base 1 HP/per turn repair rate when I can instead mount a repair module that can quite literally restore hundreds of HP per battle?
I tend to feel that under the current invasion model, soldiering and resistance bonuses aren't really worth much of anything. Part of that may just be my feeling that a good navy is far more useful than good troops in GCIII, however; after all, if you can secure control of the space around a planet, it is eventually going to fall, and under the current model it probably won't take too long for it to fall, either. Planets generally just won't hold out long enough regardless of resistance bonuses and soldiering bonuses for the goal of making the world defensively strong enough to last long enough for the fleet to regain control over the region. That, however, may just be me being biased as the one normally doing the invading rather than the one fending off a well-coordinated attack.
The diplomacy bonus is another one I haven't seen much point in so far. Trade and some treaties (especially if you focus on getting a couple early) come soon enough that it's easy enough to bribe an unfriendly neighbor to play nice for a while with a trade route or two or a beneficial treaty, and to be perfectly honest the only thing I really want out of the computer factions is their technology, which even relatively unfriendly empires are generally willing to trade. Later on, a human player's empire is probably strong enough to handle most of what the computer can throw at them even if several of the neighbors declare war, what with specialized planets having something like three times the total output of generalized planets. If the computer handled warfare better, allies might be nice, but so far I haven't seen much use in them aside from getting a diplomatic victory and a border I don't have to watch as closely.
As far as very weak traits go, I'd suggest the tourism one. Sure, it's free money, but +25% on 2 or 3 credits per planet per turn doesn't really matter that much; a halfway decent purse world can be producing ~100 credits per turn, and I've occasionally had purse worlds earning ~2000 credits per turn. Tourism just won't really cut it by comparison.
Anyone notice this or notice something I missed in my assessment?
The only thing I disagree with slightly is the Productive bonus. It's essentially a free factory (basic and level 0, sadly) on every world, and unlike research and income bonuses, every world you have will have had a use for a manufacturing bonus at some point. The bonus is a bit small to be excited about, but unlike the others it's at least useful for every world you have. It's also more useful for lab and purse worlds than an income or research bonus is for factory worlds (unless you have Ancient for +1 research on every planet for each Ascension Crystal you work, or the end of the Benevolent research branch for +5 research on every planet). Productive isn't really a great bonus, but it is somewhat more useful than the income bonus or the research bonus.
Otherwise, I agree with the assessment that these are less than ideal traits to pick up.