Is Getting Keys Worth it or Should I Wait for a Sale?

I also sell games only for keys. It's seriously the best option. You can find people interested in your games, but I don't think they'll offer you the games you want. Keep in mind that there a lot of trading sites where you can make a trade post. So, because most of the games that you ask for are a bit expensive, I will advise you to buy them during the sales.

It's because your list there is just too high tier. I mean, pretty much your entire listed bundle key stock put together may be worth one Witcher III or one MGS V key. Maybe. If you have bundle games, deal in bundle games. Asking for TF/CS keys for them may be worth a shot, but mostly only for Humble Bundle stuff, or some really sought-after game (like, for example, In Verbis Virtus was in a Groupees bundle and it was worth a lot in trades despite its bundle status). Otherwise my general experience is that people rarely give up their keys even for high-tier or even non-bundle AAA games.