A few random thoughts. You do have control over which resorts and weeks you will take but not on whether you will get them or not or when. It helps to know when certain resorts tend to deposit, 13 months out for Marriott, 2 years for KCR, for example. And you MAY not have control over whether the week starts Fri, Sat or Sun. As noted, many options are very difficult to get even if you plan ahead. I'd agree with the 2 year out recommendation. IMO, only the Sunterra, Marriott and Westin resorts are comparable to
DVC but if one needs a larger unit (2 BR), it's likely best to consider second tier resorts as well. IMO, the 1 BR is the best exchange option and the studio a very poor choice given the number of points required.
Specific to KCR, I'm not sure if all the 1 BR units are 2 BA in both sections. Traditionally KCR has been easy to get but given Shell's new arrangement with BG, similar to BVTC for DVC to CI and Cordial, I would expect that may change somewhat. Anyone wanting to trade to HI should talk to some of the independent's and see if you can work something out. It'll improve your chances as this opens up additional resorts and inventory and might save you points as well in many cases. I'd say Dial an Exchange, San Francisco Exchange, Trading Places Int, Trading Places Maui (unrelated), Platinum interchange and HTSE are all viable options. Several will allow free memberships and some will allow search first. Plus it improves the chances of getting a 1 unit size upgrade significantly. Regardless, you could check with any or all of them periodically at the same time you were doing a search with DVC and take the one that comes through first. Some of these companies have an in with certain resorts as well.
As for guessing how many points it will be for DVC on Oahu, I'd estimate you're looking at only 3 seasons with two of them being Magic and Premier and the other likely either Choice or Dream but not adventure and somewhat similar to the points at BWV, BCV, etc for those seasons.
Added: KCR charges extra for AC. Extra charges for electricity, AC, etc are not that uncommon esp in HI and the Caribbean.