No matter how hard I tried, I just could not grasp the iambic.
Iambic is not that big of a deal. There is no requirement to go full Iambic. When you are using a dual paddle key and a keyer with Iambic capabilities, it comes naturally as your speed increases. No need to force the issue. Trying to force yourself to go full Iambic only causes your error rate to go up.
When I first started using a Iambic keyer (around 1981), I tried to learn Iambic keying. I found it very clumsy and error prone. But that was before I got my code speed increased. Instead, I just used the two paddles as if they were a single paddle and banged them back and forth. And, as I said above, Iambic methods started to creep in when my speed went up. I think it started to feel comfortable with some characters at around 20 WPM. But I still don't bother with all of the Morse characters.
You might want to get a copy of
Iambic Keying - Debunking the Myth. It's a pretty good read. And, if you want to go even further, there is a such thing as
Triambic Keying. But that never really caught on.