The thing about Spyderco is that they've made a lot of different knife models over the years & none of them are exactly the same (which makes Spydies so collectable) but also makes deciding which model is most like the Endura but "nicer" is a highly arbitrary matter.
But, I just went thru my entire 140+ Spydie folder collection and I came up with the following list of knives that I think are most like the Endura in terms of blade shape & size but also "nicer."
Here's a picture of the knives (which are stacked below a Gen 1 Endura FRN which is the only version of the Endura that I own) that I think qualify for consideration:
They are (from top to bottom) with the scale material (which is what makes them look nicer than the Endura IMO) noted in parentheses, as follows:
1) Gayle Bradley 2 (CF/G10 Laminate)
2) Advocate (Titanium)
3) Hungarian (Polished G10)
4) Pattada (Buffed G10)
5) JD Smith (Micarta)
6) Calypso (Micarta)
I like them all but the one that I think best fits the requirements is the Gayle Bradley 2 but that's just my personal opinion. It is also the only knife in the list that is still in production & available to buy direct from Spyderco & its dealers.
The rest are now only available in the secondary market & most of them are very hard to find.
The Calypso & JD Smith are the original micarta versions & are not the later sprint G10 versions of those knives. The Calpyso with its 4" blade is probably "too big" for the OP but I included it just the same because I think it's pretty & not as scary as the Millie.
I did NOT include any Spydie w/a FRN or unpolished/buffed G10 scales because none of them IMO would look "nicer" than an Endura w/similiar scales on it. This includes the Opus & Stretch. Nor did I include any knives with a blade with a shape significantly dissimilar to the drop point on the Endura, which includes knives like the Swayback & Kapara.
Nothing against those knives but they didn't seem to fit the OP's requirements for a knife that is like the Endura but "nicer." Arguably, this should also exclude the JD Smith too but I included them just the same because I think that it looks so "nice."