It took me thirty-odd years to get around to it, but we climbed it in November (trip report), and it was well worth it
Grassy hills, but still with character, and great viewpoints (on the right day) for Snowdon and a host of other mountains.
Unless there's been fresh snow over there since las Sunday (don't think so?) I doubt there'll be much surviving at those heights. But there are a few steep slopes so I'd certainly stick an ice axe in the car - unless the clag's right down you'll be able to tell from the valley whether it'll be needed.
Yup they're all worth it, you get great views of the Nantlle ridge in particular.
I walked up from Llanberis over Hebog to Foel Gron, Moel Cynghorion and then up to Snowdon it's a good chance to stand at the top of Cloggy , then take the tourist path down via Llechog.
If you have an eye for glacial features you'll appreciate Cwm Dwythwch - it's absolutely enormous with four smaller cwms nestling higher within it. Looking up from the valley it's hard to imagine the scale of things but once you're up there it's well worth stepping off the line of the path to get a better view down into them.
I have Paul Gannon's book - Rock Trails, Snowdonia, in which he describes a high level walk taking in each of these four cwms, he reckons you can only really appreciate them from within. He warns that it involves traversing very steep slopes and is potentially hazardous, especially when wet. I was quite happy to keep to the usual path over the summits and peer down now and then - still pretty impressive
I've done the Moel Eilio twice. The second time was at the end of a looooong walk on a warm & sunny May day which commenced at the Watkin path, continued to Snowdon via Yr Aran & the South ridge and then took in the ridge which culminates at the hill you mentioned.
Personally, I prefer more rugged terrain, but if you like green, round, soft-underfoot hilly-type summits, then this one could be for you
, then take the tourist path down via Llechog. 
