I know exactly what you mean!!
Digressing slightly, a few years ago myself and son in law set off from Lancaster and travelled up the A roads to Carlisle, then onto the west coast roads, we stayed as close to the coast as possible, Dumfries, Stranraer, Ayr, Greenock over the Erskine bridge.
Once passed Dumbarton, it was pure magic!! Still sticking to the coast, North we went! Inveraray to Mallaig across to Skye, round the island and back over the bridge to Applecross and then ont Torridon.
My son in law's bike started to play up, so rather than screw it up completely, we decided to cut out the far north bit and cut across to Inverness and then down to Perth and on to Paisley, my mum and dads hoose!!
Sorry for going on!!
Yes, your absolutely right, the B roads are bloody brilliant!!
I will have to do it again before I get too old!!!! Haha