In reply to Offwidth:
Not sure how you arrive at this as a list of "top" routes by votes: they range from extremely popular to rarely done. But, I'll bite:
> So these are the top 5.9 valley trad routes with no aid on votes on Mountain Project ... some have been discussed, how many others do you (or anyone else think are HVS?
> CPoF
Yes, HVS. Certainly no pitch is harder. Some might feel harder if you don't climb in the valley much.
> Quicksilver
No, not HVS. Technical difficulty is consistent with difficulty of moves on well protected HVS routes, but the R in the grade should be taken seriously. Something in the low E would seem appropriate. Middle cathedral face climbing is also a special thing, even for the valley.
> Nutcracker variation start
Probably a bit of a sandbag at 5.9, but HVS wouldn't be too far out.
> Peter Pan
Sure, HVS: too hard to be anything else. If you're not used to wide climbing in the valley expect to find this hard. Lots of "valley" climbers would find this hard but grades shouldn't pander to the technically deficient.
> The Grack Marginal
> Coonyard Pinnacle
These two fall in the same category as Quicksilver. There's an R in the rating which needs to be accounted for. Technical difficulties are consistent with what you might find on a well protected HVS.
> Commitment
Yep. HVS and a fairly straightforward one. One hard move with perfect protection. If you don't want to grade it HVS, then I can only suggest VS.
> Entrance Exam
A traditional challenge for which the HVS grade was made. It's intimidating, but not actually that hard. You can even protect it pretty well with a few big cams.
> Higher Cathedral Regular
I assume you mean Higher Cathedral Spire? Sure, I'd give it HVS.
> I'd also be interested in views on 5.9 padding stuff. Most to me feels about easy 5c and E1-E3 depending on gear.
Sure, 5b or 5c. The kind of difficulty you'd find on a lot of HVS routes with runouts that bump the grades into low E. You can also easily make these routes technically harder if you fail to find the path of least resistance.
So in general 5.9 equates to the same level of technical difficulty you'd find on HVS routes in the UK but it's wise to pay attention to the style and any kind of seriousness rating if you're converting to UK adjectival grade.
To the OP. If you climb HVS in the UK you'd find lots to do in Yosemite. As others have said, work your way through the grades and get comfortable with the style. It's generally easier and less scary to make your way to the top of cracks than runout slabs, unless you're unfamiliar with the operation of camming devices. It also helps to not get tired easily.