Having gotten a fairly good handle on war-steeds, I still think those are pretty well handled overall, except that the landscape is more full of bugs than an insect zoo, and the mob difficulty is set all over the map-- a critter who is trivial when you're on a war-steed is devastating on foot. When you add to this the fact that creatures are constantly spawning and instantly re-spawing all over the place, landscape quests quickly become an exercise in learning to avoid any monsters because Eru-forbid, if you start fighting with one, you'll be fighting all day just so you can click on a stupid macguffin and move on. I like that situational awareness is important when you're riding all over the landscape and that mobs are smart enough to run for reinforcements-- that part is cool. What I don't like is seeing the glowy thing across the room I have to click on and just watching the mobs stack up in front of it, knowing that the moment I kill them all, they'll be right back there.
The mobs also appear to have a "soft aggro" mechanic going on. I first spotted this in Moria, but in Rohan it seems to have been cranked up to obnoxious levels. "Soft aggro" is mobs in your general vicinity which have theoretically not become aware of you, still moving in a more-or-less beeline fashion towards you, or towards your goal. Warbands are particularly bad about this-- they have a preprogrammed path they follow across the landscape, until there is a player character within a certain distance (200m maybe?), at which point their path immediately alters specifically to take them towards that character. When you're already questing in a mob-heavy area, having the same warband molest you two or three times when all you want to do is collect two more hides and GTFO gets really, really old.
As I've already alluded to, Rohan is also full of crazy difficulty spikes. I am currently level 87, with the best bartered gear I can find, working on quests in the level 83-85 range. Most content for me should be a cakewalk. But Rohan is liberally sprinkled with elite mobs, many of which spawn right on top of you while you're walking by, and like I say, these mobs are designed with the assumption that you're riding a war-steed. If you are on foot, and especially if you get more than one at a time, you're screwed. Even if you're not screwed, you're still stuck grinding your way through a fight with an elite, which is generally not hard, just takes forever.
Well, except for the elites with broken abilities. Such as the half-orc in Thornhope who sets you on fire for 300-500 points of damage per second, so you have to use a potion immediately, then sets you on fire again before your potion cooldown expires. Or the ghost-dwarf-thing in Wildermore who reflects more damage back at you than you inflicted on him-- on top the normal pounding on you a boss does. (Dear LotRO devs: STOP GIVING MONSTERS REFLECT. IT IS ANTI-FUN. Especially when that reflect lasts longer than the fight. At least the daywalker berserkers, you can stop attacking for the 45 seconds they reflect the damage back at you.)
And then there's Hytbold. I can see Hytbold looking really good on paper-- it's a burned-out town in Rohan that your character is tasked with fixing up, leading to you eventually being named Thane (and finishing off a murder-mystery storyline in another town). It's intended to be endgame content for solo/casual players who don't like raiding or whatever, consisting of a variety of daily quests around different parts of Rohan that give you the resources to rebuild.
That's cool, I can get behind that idea. But like so many other things in LotRO, the implementation of the idea has issues. First off, some of the quests are just damned annoying. LotRO is pretty weak at jump puzzles, because the movement controls are wibbly-wobbly positioney-witioney. So naturally, they put jump puzzles into the Hytbold quests. Another one has, through an extremely circuitous set of reasoning, you walking across a tightrope carrying a bundle of arrows, which you have to time right or a circling crow will fly into you and knock you off.
A crow. Really. I HAVE A BOW. What possible reason could I have for not shooting the crow and THEN walking across the tightrope, other than that the quest won't let me? I've faced down Nazgul! I've slain a dragon-wight and defeated the Steward of Angmar! But man, have a crow circling my intended path, and I'm out of luck.
The other thing with Hytbold is that, being endgame content, it has daily locks. Once you do five Hytbold quests, you're prevented from doing any more until 3 a.m. the next morning-- this is on top of the individual 24-hr timer each quest also has. It doesn't matter if you did all five on one day, or did one per day for five days, or whatever. I've been doing two or three in a day as I come upon them instead of chasing them down, 'cos I've still got a lot of Rohan to get through, but that leads to finishing one right off the bat one day and being locked out on doing any more that day.
Oh, did I mention that the story quest goes off on one direction while the landscape quests go off in another? 'cos there's that problem, too.
So, yeah. Rohan has issues. :-`