The general impression I have had from open theists is that they propose that if God does not know the future then our dignity is preserved. It isn't because the question as to what constitutes the nature of human dignity is obviously something that is hard to establish even amongsts all variations of theists. Just because the god you believe in doesn't know the future doesn't make that god able to confer more dignity and freedom to you, or make it easier for you relate to that concept of god because you're still not interacting with that god any more directly than anyone else.
No, my impression about open theists, indulge in a massive stereotype about the open theists I've met over the last twenty years, is that these are generally able-bodied people who can only relate to a conception of god who has as many options in life as they feel they have been given. They don't usually truly feel that their body itself constitutes a physical weakness. I have met other fellow Christians with substantial disabilities and I have not noticed, as a general rule, that these disabled Christians take huge solace or encouragement in the idea that because God can't possibly know the future He is in the adventure with us.
No, last I checked most Christians with substantial disabilities put their hope in something God has promised us in the age to come, the resurrection from the dead and new bodies. It's strange that an open theist would wish to hinge so much of our Christian hope on the inability of a god to know the future since a god who is completely incapable of knowing the future can't truly know that he/she will be able to keep his promises. After all, if God knows something WILL happen human freedom is harmed. Now I know an open theist would say that promises God makes within His character He can and does keep, but when Paul writes that God has saved us and called us with a holy calling, not according to our works but according to God's plan and the grace given us in Jesus Christ before the beginning of time ... well, that has to get interpreted by an open theist quite a bit. If you don't believe Paul wrote that then either you don't think Paul wrote 2 Timothy 1:9-10 (and I grant it's possible for you to conclude that) or you think that the statement itself, regardeless of apostolic pedigree, must be taken as an implementation of the Divine Guess. God didn't really know humanity was going to turn from Him and so Jesus was the great ultimate Contingency Plan set up before time began in case God discovered humanity actually wouldn't continue to walk in fellowship with Him. Oh, yeah, that's totally awesome.
I'm not trying particularly to be insulting in suggesting that open theists tend to be affluent white folks who have benefited from the luxury of imagining a God who is as uncertain about the values of the things He pursues as they have been but that's my spit-take on open theism. Poor people and people with disabilities realize that the Holy Spirit in an open theist conception isn't able to be the same kind of Comforter the scriptures and our Lord says the Spirit is because an open theist Spirit does not know the future and we must cooperate with God to make sure the right future comes about, which suggests that we know the right future as much as God Himself, and since nobody knows the future anyway, there you go. It's sort of like the xkcd about Macs and PCs: Hi, I'm a Mac. Hi, I'm a PC. And since we both make you do everything through a browser these days there's basically no difference between us. The browser is the constraint of time and our inability to know the future because we exist within it. A person with a handicap can see that an able bodied person who advocates open theism would like God to have the handicap of being unable to know the future despite knowing everything that can be known.
Guess what, a person with a disability already appreciates how a body has limits so for us the Incarnation is full of mystery, wonder, and hope that too many able-bodied Christians are apt to ignore. When Jesus said "Before Abraham was I am" did that suggested Jesus existed inside or outside of time? Why would a person assume a binary answer to a question about a statement in which Jesus employs the past and present to refer to a simultaneous state of being? Before Abraham was I am. The present tense "I am" is positioned ostentatiously in relationship to "Before Abraham was". If you insist on saying this can't mean that Jesus describes Himself as simultaneosly existing inside and outside of time then, well, obviously nothing I could say or mention about a biblical text would convince you anyway. I have met a few Christians over the years in person via internet who have been pretty good at saying they take Jesus seriously until the possibility that He said something they feel uncomfortable with makes them decide the evangelists didn't accurately record Jesus' words. So Jesus will bless the poor but not predict the annihilation of Jerusalem. Jesus will speak up against religious authorities but not curse a fig tree. Jesus will heal the man born blind but not call a Syrophoenician woman a dog. You know, that kind of stuff.
My beef with open theism is that it is one of the more obvious and self-involved ways in which mostly affluent white Americans want to project their own anxiety and uncertainty onto the Trinitarian god. I'm not saying open theists are worse people than others, everybody sins, I'm just saying as someone who has lived with a disability for a while that if an open theist finds no comfort in the Incarnation or the Crucifixion then that open theist has probably taken his or her body for granted more than his or her intellect. It's not that I can't understand why someone would like open theism, it's because having lived with limitations myself I can very easily understand the gist of open theism, which is to imagine that God the Father, Son and Spirit are as limited within time as I myself notice I am. Since God's ways are not my ways and God's thoughts are not my thoughts I'm willing to roll with the idea that God can exist inside and outside of time simultaneously while I can't. God the Son can be said to exist inside and outside time by virtue of the Incarnation. But I've rambled enough on that subject for the day.