This is a thought-provoking question!
Before I seriously looked at Catholicism, I would have said, “Duh, Catholicism’s easier!!! You can sin all you want, then confess to a priest, say some Ave Marias or Pater Nosters, and you’re good to go!”
Needless to say, I didn’t know what I was talking about!
Then, upon seriously looking at Catholicism, I would (initially) have said that Protestantism is easier. After all, Protestants don’t have to confess to a priest, they don’t believe in a purgation (specifically the Catholic idea, not the lack of suffering), etc. If Luther was correct (in his hyperbolic manner of rhetoric), and one can commit murder or adultery 100 times in a day with no effect on his eternal salvation, I would be hard pressed to see how Protestantism could be more difficult!
However, with some mulling on the question, it’s not so clear as it once seemed to me.
Having received the sacrament of Reconciliation, I can say that it is a beautiful, wonderful, but very difficult thing to do (or at least, it is for me). After 24 years of not seeing a need to confess to another human (at least not in the sense that confession is heard by priests). The idea I once had, that a Catholic can just say “Oh, I’ll confess this tomorrow”, while choosing to sin today, would make the sacrament invalid, as absolution requires contrition. I’m sure there are many who go to confession with this in mind, it’s not what the Church teaches us to do.
Protestants, on the other hand, do not hear the priest’s words of absolution. The tangible experience of forgiveness is missing. I frequently “tried to feel remorse” for my sins, hoping that it would be good enough to warrant forgiveness (I know this is also a bit of a misunderstanding of most Protestant theology, but without the priest there to administer the sacrament, I needed some confirmation, some emotional feeling that I was forgiven, as I had no physical one).
For me, it is easier to soak in the Catholic faith as one would soak in a healing spring. It may burn at first, may be hard to sit in the bubbling, steaming water. Once you know how to get into the water and how to let it soothe your injuries and wash you, you begin to crave it! In Protestantism, there always seems a big tendency to dip your toes in the spring and, finding it too hot, too cold, too bubbly, too still, to move on to the next spring, or to mine one yourself, digging through the Scriptures to find all the answers to your questions.
In Catholicism, I find the faith to be similar to the Gospel of John: like a river that is safe enough for a child to splash around, yet deep enough to submerge an elephant! It’s a both/and. My experience with Protestantism (in general, though there were specific exceptions) was Protestant traditions tend to be either too safe/shallow/broad or too dangerous/deep/narrow. Contrast much of the mainline Protestant denoms in the US with staunch Calvinist denoms. The mainliners often are looking to stay relevant, to engage the culture, often at the expense of orthodoxy. Much of the writings of staunch Calvinist theologians I’ve read, on the other hand, had such a stodgy feel that it was like being dropped out of a helicopter into the flooding Mississippi.
The emphasis on personal interpretation of Scripture, the perspicuity of Scripture, etc, mandates that the individual (or, perhaps a very small unit of the church, i.e. husband and wife, not even the full “domestic church”) constantly reinvents the wheel. After all, if we rely too much on commentaries, systematized/biblical theology structures, etc, we’re relying on traditions of men.
What my father and father-in-law see as the straightjacket of Catholic dogma/infallibility/unchangeable doctrine, etc, I see as a framework to grow within/upon, in the same sense that the trellis/support surrounds and protects my tomato plants in the garden, allowing them to grow higher and bear more fruit than if they were unsupported. As a Christian in the Catholic faith tradition, I can lean on the Saints (in prayer and study), and I can stand protected against the spiritual storms of life when I grow within the framework of 2000 years of faithful Catholic doctrine. Sturdier than the tomato cage, of course, this faith goes back to the Apostles, firmly founded on the Rock of Christ and on the See of Peter!
In short, I don’t see Protestantism or Catholicism as easier than the other. I do believe Catholicism to be true, so I am Catholic. Because of this, I can say that it is “easier” for me to be a Catholic in the sense that I firmly believe it’s where I’m supposed to be, and I seriously believe it is where God has led me to grow and ready myself for eternity with Him!
(I know I went a little off topic here, but I hope it was a little useful)