Where to go at 70 for decent solo exp will depend a
lot on your gear. What's easy for one of us may be a suicide run for you, so test the waters and be very careful before you commit to a new soloing spot. Study the maps as best you can and explore some if you can while invis to learn the lay of the land.
For me, I like
The Ascent in DoN -- there's several spots there that make excellent camps, or just clear up and down the trail. Dispell the mobs a time or two to make them run at a normal speed (I pull with dispell there) and it's a fairly easy exp zone for well geared Beastlords. This may not be a good spot for a player with weak gear however -- I suggest trying the lone puma that paths to just outside the zonein room... if things are going poorly, the zone is just a few steps away, and if it goes well... well, you're gold

On the bad side, lots and lots and lots of folks come here for DoN progressions quests, killing everything they see in bulk, so it's often hard to find a spot out of their way.
Stillmoon Temple has a few decent spots to set up camp at too -- I suggest avoiding the entry courtyard and the first few rooms off from the staircase, as these are pulled heavily for people doing progression tasks, and avoid the direct hallway path to The Ascent zone, as many of the game's less considerate players like to just train through. Again, dispell the mobs before you slow them (let the warder take a round or two while you do this) to keep the runners moving slow. The dojo, the temple, the bathhouse, the library, either of the gardens -- these are all excellent out-of-the-way spots to set up camp at.
Grieg's End on Luclin also has some good exp there -- the central area past the iron grate door (when coming from Dawnshroud) is dark blue at 70. The mobs have low hp, low dps, and offer about 1% AA a kill, maybe a bit over. Before DoN I gained quite a few AA very very easily here, plus tribute from the named drops -- self buffed only, I could easily handle multiples (though, again, gear makes a lot of difference -- obviously, you don't want to try multiples if you have trouble with a single

). I don't recall any ever trying to run, and the spacing of the mobs makes it ideal for solo or small groups to pull. This was a great spot, because the mobs allowed for fast low-stress kills that allowed the AA exp to add up fast
Bloodfields and
Harbinger's Spire in OoW are about equal in terms of mob level and difficulty -- the difference being that Harbinger's Spire has Girplan and Dragorn, while Bloodfields is Muramite models. The procs from the two types of mobs are different, so go with what you resist the best. At 70, mobs in both zones are light blue near the zonein from Dranilk's Scar, scaling up to dark blue the further in you go -- so the further in you go, the less solo-friendly the mobs become. Exp is the same in both zones -- a bit under 1% AA for light blues, a bit over 1% up to about 2% for dark blues.
Nobles Causeway I had mixed experiences there... I could solo the Murkgliders in the valleys, but never had good success with the Muramites or Dragorn. Downtime will be heavy here -- I suggest a C and an Oak if you can get it to help with mana regen. You can test the waters here by dropping down into the valley to the left of the path near the Dranik's Scar zone and pull the first Murkglider you see a short ways down... pull him far back, as they will try and run, and there is a wanderer that paths down close to where the first Murkglider spawns. Exp per kill here was good, a bit over 2% a pop, sometimes 3%, but the kills-per-hour was low, making this zone unsatisfactory for me personally.
The Elemental Planes, such as
Nightmare, offer some fast easy solo experience too. The mobs are fairly easy, ranging in con from light blue to dark blue, and giving about 1% a kill for light blue and around 2% for dark blue. Pulls can be fast, downtime is light, and it's decent exp-per-hour... but respawn can be slowish, especially if several groups are hunting there, and pulls can often bring adds due to all the wanderers.
In Taelosia,
Riwwi was good solo exp too. Personally, I found this no more difficult than Nightmare... but the gear plays a large role there, as others call this zone a pita

Exp is about 2% a kill.. best strategy, choose a zone tunnel system and keep it cleared -- this keeps you close to the zone if you need to bail, and helps you avoid wanderers. Set up at the end of one of the side canals that branch off the straight path to the zone to avoid the inevitable trains.
The kennels near the zoneline in
Quinimi were a popular spot for me before Riwwi also, though I don't recall if they were blue or light blue at 70. Each kennel can be single pulled, and many groups or soloists just set up near the Natimbi zonein to avoid wanderers. There are three static spawns between the zone and the kennels, plus two wanderers that path into the valley. On the bad side, those wanderers are placeholders for two named mobs that are needed for the BiC quest... they're mean. Very mean. If the placeholders are nonaggro (stonemites), just leave them alone, as these guys spawning on your head is NOT fun

I hope some of that is of help to you
