For people who use the Steam trading sister site, is there some sort of meta?

When I was a noob and first posted there, I had an influx of people looking for particular games that were selling for high prices on G2A and places like that. Honestly, I'd check their G2A price. Know where you stand. People will try to trade you a low-value bundle game (because it's been bundled many times) but might have an equal price to yours on Steam, then turn around and make a €10 profit on the game they got from you. Steamtrades is full of low-ballers, so be careful.

You've guessed it right, most of the giftlink buyouts of what is considered triple-A or well known and sought for indies are for reselling on g2a etc. But it isn't uncommon to be requested giftlink even from nonresellers as it's little bit safer (no risk of used key). In general, after cross region steam gifting ban it went a little south, there's a lot of people purely for profit instead of convenient game swap, it's almost impossible to get "priced" offers as everyone seems to try to flip bundles for at least double the direct buy price.

It's so hard to know what games are priced at that now I only look at those with price charts so that it's easier to know how much to offer. Gift links are much safer no matter who you're trading with and especially for those with low "steamtrade rep", so it might not be that they're reselling but to be sure that they're getting a good key. Of course for good/bigger titles, they can simply be resellers. If you just want to trade for games you want, barter vg is probably easier than steamtrades.

Yea if someone asks for a giftlink it means they don't plan to redeem it right away and are probably planning to resell it.
If you want to trade games without thinking about grey-market prices then you'll have the best chances with new traders.

some of them requesting gift links (implying they plan to retrade them)?
[...]
I just want to get rid of stuff I'm not that interested in.

You'll have to make a choice there: do you want to just get rid of stuff, or do you want to maximize "profits" while getting rid of stuff? If you just want to get rid of stuff, I'd say don't bother with that. If you want to maximize profits, I guess you'll have to look into "grey areas" that others already referred to. It's work, and perhaps more risky, so I guess that's why there are some margins involved... Personally, I can't be bothered so I just give my leftovers here, or sometimes I trade them on Steam forums if I can't afford the loss.

Giftlink preference is normal as not only for reselling, but also if the trader plans on gifting it to a friend/here on steamgifts.

As for value, G2A is a pretty good indication as everyone else says. Also one thing anyone should realize as well is that if you wish to trade your bundled stuff for something that has never been bundled before in your wishlist, you will always expect to 'overpay' for the other trader's profit, as no one really will be willing to buy such games without some kind of profit to themselves.

Bundled game for bundled game, however, you can justify trade value equality with their G2A prices fine.

Just come over to barter.vg. Steamtrades is for normies.

is funny how users talking about fairness and G2A prices to check, let's buy bundle for 10 bucks and trade or sell it for 60 bucks it's fair
no G2A price isn't fair, did you paid 60 dollars? No you paid 10 so asking 10 dollars just for one game from all isn't fair.
I don't really understand to logic of guys who telling you to check G2A? Fairness as long as it's good for them only.

Actually, if you're a relatively new trader on SteamTrades, lots of traders will either try to lowball or outright scam you - hoping you're "green" enough to not know the rules or how the site works.

What the user above me tried to tell in much more pleasant terms, the meta of SteamTrades is who gets to be the bigger asshole who manages to out-asshole the other. Even if your trading partner is actually a very pleasant person and a good guy/gal otherwise, trading there is an asshole-off. Trading on SteamTrades is like playing DayZ in this regard.

mostly useless, full with resellers who want to rip you off and very few real buyers or traders. barter.vg was better some time but its now full with resellerstoo, whose spamoffering tier1 crap or other low bundle games for your unwanted tier3 or expensive monthly game.

Sometimes still possible to get real offers tho, but if a game got bundles more than twice you probably can throw that game key out.

pretty sure it's because I'm a noob but I don't really care for g2a and this "grey market", and instead just go visit isthereanydeal and check to see if a game has been bundled, and then check how much it is on steam for a regular price, and consider how high priority it is for me/how high demand on ST, and then decide on how much it really is worth, personally.

So overall it's more of a "personal worth" thing for me. must be because I'm a noob

oh, and also may be because there's no PayPal in my region so I don't care about PayPal prices/g2a prices...

I read here some weird arguments. First of all I just can give you the advice to trade with reliable Traders with high +rep, too many of those new accounts are just made to try scamming noob Traders, so be careful. And if someone is only online with his mobile it´s safe to trade with giftlinks, because the Trader owns the link after clicking the link and can redeem it later and the 2nd thing why some prefer giftlinks is just because Humble gives you a Region lock warning if there is any, lock but doesn´t by revealing the key, so thats also safer. Ofc there are some Resellers, but it´s easy to find out just by Looking into their threads and reading some comments. Oh, and for the Price... yep g2a is a good place to check the Prices, but Overall if its ok for you and the other Trader and everyone gets something he/she wants everything is fine..

Wouldn't even waste your time. Unless you want to be lowballed and offered games worth 1-2$ for games that are 10-20$