For LEO, I simply stake any bits that I've got and then delegate it to a curator. I'm not big on it, but I have a small growing stake to take advantage of any success in the far future. So there's my LEO strategy.
As for Splinterlands, I've got quite a few cards and don't intend to sell them at all. I play it everyday and just farm the rewards. We'll see if it goes a to new high just as it did during the last crypto boom. If it doesn't, well, at least I'm enjoying the game everyday. I'll just think of it as entertainment expenses.
As with all things anyone wants to think of as an investment, the golden rule applies. Don't go all-in and only put in what you can afford and are willing to lose.