I second that request and would also like to suggest more control on repeats, perhaps the option to specify different dynamics or alternate notes (pitch and rhythm) depending on which # of the repeats is happening. Ties should definitely default to the behavior davidlimburg requested.
As a workaround until this gets added (if it ever does) I'd like to suggest the following which works for me in most cases. If the repeat causes such a break in ties I simply add more bars to the endings retroactively so that the ties remain intact. It's not the best for a printed score but it does solve the problem for making a recording.
The workaround for my request is not to use repeat signs and just copy the measures to produce the result of a "repeat".
I hope this helps!
