Seeker7, sorry this is so long ....
I think we have to take one step back to help you understand the plan of salvation and that is asking you what you think "bliss" is? For most Mormons I know, bliss is not a finite state achieved. True eternal happiness for most Mormons is to have eternal increase. To be able to have eternal increase all of these things have to happen. If you believe that "bliss" is a single state of being, then I can see how you would ask why didn't God just put us into that state to begin with.
There is one thing God or anyone can't do and that is to realize something has been done before it is actually done. Even knowing that something will happen in the future is not the same as knowing that it has. In other words, you can't get credit for potential. You have to actually complete the act to receive the glory or happiness or reward for that act. There is no glory in saying that I could do this or that. This is why we use the words "bring to pass" a lot. To bring to pass the immortality and eternal life of man.
The Celestial Kingdom, at least this is my belief, is going to be full of people like the prophet Joseph Smith, they are always on Gods errand. They don't stop to rest and they find happiness in that work. They hunger and thirst to understand how to have eternal increase, knowing that it comes by actually living and doing His work. Eternal happiness is having the ability to keep growing, (which to me means still working hard) after this life. If you do not want that kind of "lifestyle" so to speak, God will not give it to you. All of our latter day prophets that I know about have that characteristic, they would be hard to slow down, to take a break.
The Prophet Joseph Smith taught: "When you climb up a ladder, you must begin at the bottom, and ascend step by step, until you arrive at the top; and so it is with the principles of the Gospel--you must begin with the first, and go on until you learn all the principles of exaltation. But it will be a great while after you have passed through the veil [died] before you will have learned them. It is not all to be comprehended in this world; it will be a great work to learn our salvation and exaltation even beyond the grave"
Think of all the things that have really made you happy in this life. Sure sitting on a beach in Hawaii under the sun is fun but I've felt most happy when I have achieved something I've worked hard for or watch my kids achieve and meet milestones. To have the ability to continue to grow and have purpose is true happiness. Even if God were able to give you all knowledge the one thing He couldn't give you is the knowledge that you have done something you really haven't. And just knowing that you have the potential is not the same as doing it.
The other part of eternal happiness to understand is family. This part of happiness is easier to understand after you have a temple marriage and have children. God said of those who were not willing to pay the full price of exaltation through full obedience to his whole law: “Therefore, when they are out of the world they neither marry nor are given in marriage; but are appointed angels in heaven, which angels are ministering servants, to minister for those who are worthy of a far more, and an exceeding, and an eternal weight of glory.“For these angels did not abide in my law; therefore, they cannot be enlarged, but remain separately and singly, without exaltation, in their saved condition, to all eternity; and from henceforth are not gods, but are angels of God forever and ever.” (D&C 132:16–17.)
Understanding what eternal happiness is first, helped me understand the Plan of Salvation, realizing that it's not just a state of mind, its having the same purpose and errand as God. If I stayed in the state I am in right now or even before this life, like being stuck in the 4th grade or something, my happiness is limited. My salvation and fullness of joy comes from getting to that place where I can have eternal increase (family and knowledge) and happiness. "Well done; . . . thou hast been faithful over a few things, I will make thee ruler over many things: enter thou into the joy of thy lord" (Matthew 25:23). Joy comes from having an increase in our responsibilities.
Seeker7, hope that helps you understand the specifics of the plan.