My biggest failure and challenge with ikkyo omote is to keep the extension of my arms. Like many, I have tended to push down on the upper arm while pulling up on the lower arm. If I simply extend both of my arms fully and move forward from my center, Uke remains unbalanced and goes right down.
I have friends from another school who routinely perform the "bump" into the armpit and slide back out. That works pretty well until Uke decides to use that movement to reverse Nage and "sweep" the legs into a takedown.