Bitez or perhaps Fethiye/Calis both would seem to fit the bill. Both are handy for other resorts via Dolmus' so you can get a bit of variety.
Side is also comparable in size and entertainment.
My own opinion anyway but as I didn't like dalyan very much perhaps biased.

Like you we loved Dalyan, it was our first visit there, going back next year.
We have been to most of the resorts and found Dalyan the best as you say just right and scenery to die for.
Try Olu Deniz, beautiful beaches, enough going on, also dolmus service great for getting to the other resorts,, Calis/Fethyie/ Hisoronu/Kas .
The old town of Kusadasi is nice.happy hunting, you just dont know till you try.

Just a personal opinion but if you love Dalyan and didn't like Kalkan, then you will probably hate Calis! Horrible beach! I doubt if you would enjoy Hisaronu either.

Olu Deniz might suit but have you considered Patara...or did you visit it when in Kalkan and were not impressed?

We live in Dalyan and love it here. We'e just got back from 3 days in Ceşme and thought it was a nice place, completely different to Dalyan. Scenery is not as green and there isn't as much of it to soak in, it was much busier, more built up. But on the plus side it is a Turkish focused resort and has a charm to match - didn't see one advert for an English breakfast, the food there is Turkish and not the international mix you get here. Also its slightly cooler thanks to a constant cooling breeze.

As a side we went to visit the Dalyan that is next door to Ceşme and it is nothing in comparision to our Dalyan, it is simply a town full of holiday homes and nothing much else.

try datca..... there are a few hills but most is on the flat.....

my god please dont go to calis , worst place ive ever been too and thats saying something seeing as ive been to kavos and laganas

We love Dalyan too and also found Kalkan disappointing. We went to Yalikavak on the Bodrum peninsula 3 years ago and quite liked it there. There is an upper and lower part of the town, but most of the hotels and restaurants are on the lower, flat, part.