1) along the A-road into Richmond on Day 3. Adds 4 km, less climbing - it's the route all local cyclist take as it feels faster, and it probably is faster.
2) Day 3: dodge the 1:3 concrete bank at Littlebeck after RHB (adds 100 m , 70 m less climbing - more importantly, it’s straight across the A169 rather than mixin’ it with the tourist traffic down Blue Bank). Anyone who hasn't ridden up Littlebeck should take the official route and ride it, but I'd then recommend going up to the top of Blue Bank and right down into Grosmont, which is a glorious descent at ludicrous speed into the village, just watch out for the junction...)
3) Day 3: along the south of the Esk between Grosmont and Egton Bridge, rather than hacking up to Egton village and down the 1:3. I’m assuming AC doesn’t know about this route! It’s half a k shorter with 60 m or so less climbing (all according to RWGPS). You cross the Esk at a proper bridge, then there’s a big ford, but with a FB at the left. Still hilly enough to keep you honest, though.
4) Day 3: cut off the corner at Keldholme near Kirkbymoorside. Probably not worth the bother, but you might as well have it - signs say Keldholme only. Saves about 200 m, negligible impact on climbing.
5) Day 2:
alternative crossing of the A69 after Hexham - mostly dodging the A69. It’s a bit shorter but a bit climbier. Edit: my tame local Mick (who is riding the event and lives about 6 miles from Hexham) has pointed out that the locals use a tiny bridge over the A69, then rejoin the A6079 just before Acomb. You can see it
here, and Mick reports it being a bit gravelly, so blame him if it's crap, but it can't possibly be worse than hacking across the A69 at Saturday dinnertime.
6) Day 3 - I've left the route through the lanes from Helmsley to Ripon as it's considerably more pleasant than flogging along the A170/A61 - but the main roads are dead easy route to follow if you prefer, and they're not likely to be very busy on Sunday evening.
7) Day 4 - along B-roads to the west side of the Lune rather than along the A683 (which was 'orrible last year with loads of wagons trundling across from the A65). A little bit shorter than the A683 too.
Day 2 - I've routed along the shortest route from Hawes to Stanhope, which is via Buttertubs and Tan Hill, then the OFFROAD section across Sleightholme Moor. If you do this section, you need to be aware of two things - firstly, the substantial bit of offroad. It's no more than gravelly, but it's downhill, so you need to go cautiously. Second, there are very few places to eat. The only likely place would be Tan Hill itself, but they do breakfast, so if you go this way, you would need to give them a call and book a breakfast, otherwise you could be living on body fat from Sedbergh to Stanhope. Obviously, the below bit about eating in Barnie wouldn't apply - you could roll down to Barnie to eat, but it would be a detour from the more direct route via Cotherstone (where there's a cafe, but it doesn't open until 10)