I'm not sure you can attach 21st century sensibilities to a story set in the 18th century and written in the mid 20th century. Don't all bonkbusters and bodice rippers have some morally dubious bits in them?
In the first adaption with Robin Ellis, Elizabeth resists and then sort of says Ross! all dreamily as he takes her. I took from that that she secretly wanted him as much as he wanted her but was resisting because that was what 'good' women should do. But no, it doesn't fit 21st century sensibilities.
I agree with the post above that Ross (especially the Aiden Turner incarnation) rather comes across as a turd, above the law, both legal and moral. His plea to Demelza (before she thwacks him) along the lines of 'I had to do it, can't you see?' was his lowest point for me.
Warleggan has too much of a chip on his shoulder and a persecution complex for me. Personally, Dwight Enys has always been my man. 'What do you want to know?' is my favourite swoon moment.
As for Rowella, I always assumed she was another of those horrid misogynistic tropes: the scheming nymphomanic.