Hello BeStill,
Yes, it is indeed very true that a Bible must be understood to be of any use. I'm glad you made good use of yours. In fact, I started out reading The Living Bible, also, as a child, but for some reason the King James never really gave me trouble (though I did not until I was much older understand some of the expressions, but the lack of understanding the fact that "bowels" related to "feelings" for example did not really hinder me - that sort of thing). I still have my old Living Bible and plan to keep it all my life, God willing, as it is very dear to me for sentimental reasons.
The EOB is not part of any online collection like Bible Gateway, afaik. It's an English translation, done by the Greek Patriarchate I believe. I downloaded my copy for about $3 - I don't have a print copy.
There are a couple of things being discussed in this thread. Yes, I think the OP is asking mainly about the formal prayers of the Church. The usual objections by most Protestants is against "vain repetition" because they are often taught that any repetition in prayer is vain, according to that Scripture. But my position would be that repetition is not automatically vain, since Christ repeated His prayer in the Garden.
Vain prayer is something else, and would of course be a problem.
Saying prayers by rote (with little mental involvement) would be a problem.
Formal prayers said in this way would be of no benefit, and indeed, most Orthodox would tell you they can be damaging - if for no other reason than that the intent of prayer is communication with God, and if one pays so little attention to God while praying, this can be spiritually destructive. (There can be exceptions, such as when a person is in intense physical pain and the words and the action of prayer can be a comfort, even though the mind is essentially unable to really pray in such a difficult circumstance.)
The formal prayers are not meant to be said mechanically while praying though. They are meant to be made one's own prayer.
I have found great benefit I never expected in praying the prayers of our Church. Sometimes I want to praise God and I don't have the words to magnify His greatness as my heart desires - and then the words of some of the Saints in their prayers beautifully express what I want to say. If you've ever prayed a Psalm and found great comfort in it, then maybe you have experienced something of this. Not only that, the prayers are so rich and expansive that I have learned from them and been shaped by them, and had my attitude of prayer enriched and deepened by them.
No, they should never be prayed by rote. (Mechanically, without real involvement.)
This is a sort of side point, but I was interested to learn that while there are certain prayers that are always prayed every Liturgy, so a priest recites the same things every time he does the service - the Church actually forbids him from reciting them from memory. Even though he surely could - I've memorized them myself from hearing him pray them. But he must always read them, because the Church doesn't want to risk them being a simple recitation. That is part of his reminder.
Anyway - it is certainly not required that anyone pray them. They are simply tools that are there for us to use. But to be honest, at times I find my prayer much more focused and deeper when I'm not distracted, casting about in my mind for how to say what I want. But I pray both formal prayers and extemporaneous prayers every day. They each serve their own purpose. But the formal prayers are very much my own, real prayer, even though someone else gives me their way of expressing.
I hope that makes some sense.
I pray you have a good night as well.