hard for me to be too optimistic. we've seen too many great proposals come and go over the years, and some solid proposals dumbed down to another ugly uncreative short brown box with tiny windows.
that lot next to CW moore is a HUGE plot of land. right now it's an eyesore parking lot with dirt along front street, so any decent/attractive development there would be a welcome change.
as for a new tallest, i'd love to see a building that's a TRUE tallest and that stands out more--not another one that's 2 feet higher than our current tallest. to that end, hopefully we'll get one that's at least 400 feet to the roofline, and may be a crown on top that reaches higher.
as for location, i still think the spot BoiseAirport indicated next to the CenturyLink building would be ideal, especially if it's a mixed-use hotel/condo with easy access to the convention center, grove, 8th street and other downtown amenities. here's the rendering he did of that location:
add another 50-100 feet to this rendering, and it'd be a solid and true tallest.