Unless you plan to play more than 20 rounds in Scotland, you ARE wasting time on the inland courses.
Loch Lomond and Gleneagles Kings are great courses & if you have time you should play them. Otherwise, I wouldn't cross town (much less an ocean) to play an inland course in Scotland.
Think about it! St Andrews, Muirfield, Turnberry, Cruden Bay, Royal Dornoch, North Berwick & Machrihanish should all be played twice & then you MUST play Kingsbarns, Royal Troon, Prestwick, Carnoustie, Western Gailes & Gullane #1 - that's 20 rounds & we still haven't seen Brora, Royal Aberdeen, Montrose, Lundin, Elie, Nairn, Crail... Do you really have time for Lanark?
Seriously, you shouldn't try to see it all in one trip. Pick a base area to play as much as possible for 3-4 days then move to the next base. If this is a once-in-a-lifetime deal (even if you think it is, it won't be!), St Andrews HAS to be one base. You should play SA Old/New, Kingsbarns, Carnoustie, Lundin & Elie before you even think about Ladybank. Then,
- if you've only got a few days left, I would move to Turnberry / Troon / Prestwick / WG.
- if you have more than a few days, drive up to Cruden Bay & play it 2 or 3 times before driving over to Royal Dornoch.