just to offset a bit about scrum being bad: I have used SCRUM over 15 years to run teams and it worked. Most of the problems I am hearing on here are culture problems and no process can fix that. Regarding planning, a day per scrum is normal - sometimes longer, you have to use your judgement to determine when to move from design to implementation. Also, heavy use of spiking stories to learn enough to create the right design is important