It's not too late yet
If you don't have any cards from the previous set released on splinterlands.com, there's no reason you have to force yourself into buying only Chaos Legion cards. Do you like the game? Are you taking profits? Then by all means, grab Untamed monsters. Beats the price of renting them for a couple of years.
Untamed cards aren't that old like Beta, Alpha and most Promo cards. Their price is still escalating, so getting some is a good opportunity, specially if you're keeping track of your preferred strategies. Not to mention, you can always rent them to other people yourself! You'll make more money from renting them out over time, as their price slow but surely increases.
Last but not least, Untamed cards still provide collection power. Double as much as Chaos Legion. Grabbing them before prices skyrocket towards liquidity threshold is still a good opportunity - considerable profit is still profit, even if it's not tenfold.
It might be okay if you skip summoners, though. Aiming for silver or bronze league card levels is a tangible and very helpful goal to those looking to win tournaments. Rare cards are particularly cheap, as they're not as expensive as epic monsters, despite being generally very useful... And you only need 25 bcx to max them in silver!