I could see the argument for +1 to Research or +1 Production as alternative picks, but I do think Fantastic Traders is better than say, the straight-up 0.5 BC boost. For instance if you tend to run into planets with native lifeforms that can only be used as farmers, you can get a credit flow rolling when the game would otherwise assign you with 1 BC for the single "true" colonist. Of course it's always better to use extra food to support extra scientists or factory-workers, even if they may be off-planet, but in cases where production is poor it never hurts to have a supply of grain ready to go. It's really like having food act as an alternative trade goods button.
Something else to mention is that I believe the food enhancing techs tend to come faster than the production-related ones. So it doesn't amount to just a penny here or a penny there, it's more like 8-10 food per colonist. That usually means 4-5 extra BC per colony even if you don't want to go full bore with a grain surplus.
Your example is pretty weird, if you get the natives, you free your farmers with them, not use them as "bad gold deposites" (you have to use them this way only if you are lithovore, as the only drawback there). You earn money by growing your colonists, not by selling excess food. Straight +0.5 BC (if you mean money bonus racepick) is absolutely incomparable in power with FT, as its a good useful pick actually, especially if used with Democracy (as its the way it usually do). In general you grow a food on a specialized worlds, where food is good (ideally some small poor gaias or so), and use a freighters to ship it elsewhere. The rich on production production planets build a ships, poor worlds do research, small bad planets do housing to ship the produced population to a constantly colonizing new planets (aswell as exceeds from regular growth from "normal" planets). To spend a whooping 4 picks (1\5 of total!) in hope of getting few extra BC from natives is simply nonsense.
Usual research path for non-blitz races is Lab\Autofactory and only after that is coming Soils. Actually the food balance in a game is really bad, as you need to have at least 3 food per colonist at start (if you want a playable race (by playable i mean actually playable, not just "able to win some impossible AI's", as its not a problem at all), and there is only few special races as exclude here). There is simply
too few food in game, you cannot rely on selling it, you need it to enable more colonists instead. And by the time of 8-10 food per colonist output is reached - game is over for long-long time ago already. And extra 4-5 BC per colony is simply 2 cents by that time. Fantastic Traders could be used to channel a prod into money using trade goods, but its slightly different thing, and again, worthy about 0.5 picks.
There is some educational video to see how non-blitz moo2 game is playing (proper economic development):
http://forums.civfanatics.com/showthread.php?t=534483
I've been meaning to try Tactical, the part of it that really gets me though is getting used to the extra production costs of having to refit the ships with new equipment. It seems like Alpha Centauri in that respect where one really has to know "when" to build and upgrade their military at key points in the game.
I notice the auto-designer too tends to use far too much ship space for carrying bombs, seriously I don't think more than 10 per ship is needed in any decent-sized fleet.
Exactly, to know when and what to build
is the game. Auto-design is very bad, and one of AI weaknesses is using it to build the tin cans. Sometimes you need to build special bomb ships, but in non-modded game bombs is too weak, to be used seriously (actually its many other weapons being too strong, accompanied with too weak shields and planetary defences overall). But most ships have no bombs at all, or have exactly 1 bomb, to prevent ship from "doneing" after the shot (and also for actual bombardment too, sure).