So, I attended my first Eastern rite liturgy this morning. I could, quite subjectively, list the things I liked (lots of movement, participation, fluidity) and the things I didn't like (most prominently, my arthritic knees longed for many more well-defined moments for being seated). But there wouldn't be much point in that, now would there? The only possible observation is simultaneously the one most obvious and also the most subtle: it is an entirely different world.
The following contains many words that spoke most directly to my experience:
The way we approach liturgy and the values and expectations we bring to it may serve as an example. Your liturgy represents a way of responding to the greatness and the holiness of God's presence: a certain kind of sober reserve and directness and an unwillingness to "waste time." In other words, you bring many cultural values and rules of polite behavior for receiving any dignitary and apply them to worship. We do the same thing: it's simply that the rules and values we bring with us are different.
Good Roman liturgy is orderly; clergy and congregation come in, go to their places and stay there until needed. Nothing is more destructive of good Roman liturgy than someone moving around out of place "trying to be helpful." Good Roman liturgy is concise; your liturgical texts say what they have to say and they end. Take the collects or opening prayers of your liturgy as an example. They are brief and virtually all follow a model which I might typify as "God, because this is so, we ask you to do thus and such. Amen." Your Mass may be quite simply recited, or it may be quite elaborate with choirs and musical instrumental. Variety and creativity are values for you, and if you live in a typical parish you have a liturgy committee which spends a lot of time selecting hymns, planning the important liturgies of the year, etc.
We bring a different set of values to our Liturgy and we follow eastern rules of politeness and hospitality. We greet the greatness and holiness of God's presence with ceremony, every flattery. Liturgical texts are long and God can not be mentioned without including a few adjectives referring to God's goodness, mercy, power and providence. You may find our texts as prolix as we find yours terse.
I wish I had something meaningful, even brilliant, to say, but I don't. Different world, different values.