As Wasleys already mentioned, there is work going on at the Uig ferry terminal, which should be done by the time frame when you expect to be in Scotland. Fingers crossed! The Mallaig to Lochboisdale route on CalMac is actually 3 1/2 hours, which would be your best bet if Uig is still closed. You could take the Armadale to Mallaig ferry, then take the Mallaig to Lochboisdale ferry, if Uig is closed, and if you are visiting Skye first.
Your other option, if Uig is open, would be to take the Uig to Lochmaddy ferry, then drive down through North Uist and Benbecula before reaching your final destination. It's a very attractive drive, with the possible exception of the Benbecula portion.
Again, if the Uig pier is open, you could travel from Uig to Tarbert (Harris), check out some of the world class beaches there, then take the Leverburgh to Berneray ferry and travel down through North Uist and Benbecula, as above.
The ferry from Oban goes to Barra, so you'd still have to take a ferry from Barra to Eriskay, before driving on to South Uist. Oban to Barra (Castlebay) is the five hour ferry voyage which Wasleys mentioned. That route is also a bit more expensive than the shorter routes.
All of the ferries take cars. They are, after all, the lifeline to many of the Scottish islands.
We stayed at the Temple View hotel in Carinish, which is at the southern end of North Uist, and not too far from South Uist. Good location, and the food was quite good.
To be honest, there is not a whole lot to do on the Uists, unless you enjoy hiking and communing with nature. Thre are some absolutely gorgeous beaches, and the Balranald Nature Preserve on North Uist is more than worth the price of admission (it's free!). You could spend hours there. There are some ancient sites, including the ruins of early churches Howmore and Teampull na Trionaid. There's the Our Lady of the Isles monument on South Uist. But the best part of the Uists is hiking on the beaches and sometimes the machair. (The machair is very fragile - best not to walk where signs tell you not to)
The main population centers are Lochmaddy (North Uist), Lochboisdale (South Uist), and Balivanich (Benbecula). Of the three, Balivanich would probably have the most to do outside of nature activities. Lionacleit (Benbecula) has the only public indoor swimming pool (as far as I know) in the Uists.
If your spouses have access to the car while you are golfing, there are probably sites they may want to visit while you are out enjoying yourselves. In Scotland, golf is never "a good walk spoiled." The scenery at every course is magnificent!
Have a wonderful time in the Uists.
Best wishes for your safe travels.
p.s.: As an addendum to the above, it appears that Transport Scotland and the Highland Council have agreed on March 13th as the initial end date for the first portion of the Uig terminal work. So if all goes to plan, you should be able to take the Uig to Lochmaddy ferry with no worries. So disregard all those other recommendations. Unless you want to take them, of course!