Valid concern. A lot has changed with Splinterlands since it first came out. There is a bent towards paying-to-earn. And with the latest upgrade, that is is even more evident. The more you have invested the more rewards you could potential earn.
I just checked out your deck, and I did not see any summoner cards.
Yes, I purchased a Summoner's Spellbook. However, you do not get actual cards (to own) in the Spellbook any more. It's more like you are renting the cards. Since I have not been rewarded with any Summoners, effectively all of mine are level one. Therefore, it would not do my any good to try to level up any of my other cards at this point. In that vain, they are basically forcing you to invest not only in your Summoner's Spellbook, but also in Summoners if you want to advance in any way.
Sorry for the late reply. When I first joined Splinterlands, you received the cards from your Summoner's Spellbook. A lot has changed in a short time. If you have any interest in playing Splinterlands long-term, summoners are definitely where you need to invest first (the point you made above).
Do you think you will stick it out and keep playing? Do you feel that the barrier to entry for new players is too high?
With the fact that you can earn cards for free that have value, I am planning to continue playing. I have also been the beneficiary of some giveaways that have increased my inventory, so I am slowly beginning to accumulate some monsters. It looks like if I sell my higher valued cards (I got a couple of gold foils), I should be able to start buying summoner cards (possibly even to the point of upgrading) which would allow me to start making use of higher level cards.
I also have a love of card games (I have been playing Hearthstone for years and I play a similar Christian card game called Redemption offline). However, I would think the "barrier" would probably be a hinderance for someone that is not familiar with TCGs and would likely lead to a loss of interest. Whether that would happen anyway is anyone's guess.