Just to correct a little misunderstanding you seem to have here....Pre realized she is pregnant just before Anukom marriage which is like now 7 months ago in serial time. Way before Bajaj's entry.
With regards to Mr. Rochester IMO Mr. Bajaj this season or last season resembles Mir. Rochester in an alternate universe only. I literally see no core resemblance between the two.
And as we all know ITV dramas may start with a certain characteristic loosely in mind for those introduced midway to the serial..and as things turned out. there was literally no resemblence to Mr. Rochester with regards to what was shown of Bajaj nearly 90 percent of the time even in S1 and this time there is literally nothing right now.
Don't think so hard about characters by these Cvs dear...The way the serial has fared story wise and character arc wise, for the last one year now, its quite clear to us, the furthest they think with regards to the story progression is maybe 2 weeks maximum and they have changed tracks and characters overnight left, right and center.
PS: Edit: if we actually look at the characteristics of Bajaj as shown right now it falls more into a mix of Bertha (a phyco villian) Mr. Broklehurst (an evil villian) and Blanche (Envious villian).
The only resemblance to Mr. Rochester is that of being a man with children in need of a nanny which is obviously Pre. But all the character traits are only relatable to the different categories of villians in Jane Eyre.