Don't you think it will be too "hasty" and rushed then? Since lengthy parts are said to be mostly action, won't there too much of it and too little plot / character development? I once tried to imagine BEN HUR, trimmed down to 150 Minutes and it creeped me out because I could easily imagine what parts would be missing if that cut would've been made by the producers because they always think that the audiences just want action, action, action. 

Regarding your "suggestion": Unfortunately, I got the impression that new films are not allowed to run longer than 160 Minutes when released theatrical today. The biggest exceptions (in commercial cinema) of the last years probably were the "four Jacksons" (Lord of the Rings 1 - 3 and King Kong)... I often cry out for the good old times, where it was quite common for mainstream movies to run three hours, to come back but they probably won't.