I think we're on pretty similar wavelengths as far as Umaben's character is concerned. Of course, there are dominating MILs in most of the current saas bahu shows on air but as far as I know, they have some reason or justification behind their actions... of course, some are purely mean-minded ... like the one in Housewife Hai? I don't follow any of the shows, so I really have no idea why the clashes happen. I did follow one show, Dor, recently, where the MIl wanted a working DIL so that she could take over her salary ... when the DIL kept the salary for her maayka, the MIL became wicked.
But here, because the rest of the show is very realistic, Umaben's character seems the only odd one out in being larger than life, like most soaps, rather than close to reality, like the rest are.
Also they have not made it clear ... what is her motivation? Is it just her ego and pride? Is it the greed for dowry from Thakkar Bhai? Is it vengeance and dislike only for Chhanchhan specifically?
If you look at Umaben within her own family, she is not evil towards her bahus. She controls them with a mixture of carrot and stick, especially for Ranjana, who is greedy and kaamchor, and with simple fear for Sanjana, who is simple enough to be terrorised. She is fairly decent with Kaumusi, apart from the usual barbs about how wonderful she is and how useless her bahus' maaykas are ... fairly standard practice among many MILs to criticise their bahus' families.
She keeps her sons under control as well, but through her husband ... the moment anyone o questions her, like Manthan did, Babuji supports Umaben's decision, even if he is not aware of the entire truth. So Babuji trusts her completely ... because of a time when she put her own dowry down to save the family from ruin. So there is a reason and foundation to his trust on her. But why she does not trust her own sons and keeps secrets from her own husband, that we don't know yet.
Umaben has projected her self as a social worker, leader of Mahila Mandal, a lady with progressive thoughts ... she tells her MM ladies that her bahus are free to join computer classes, but they don't want to ... to her bahus she portrays that she doesn't bother about pallu etc, it's Babuji who is strict ... again showing them that she is a progressive lady ...
I think she is not as conservative as the rules she enforces, suggest ... her rules are more to assert her domination and her authority than out of any sincere belief. I could be wrong here ... maybe she is conservative, but since she portrays herself as being progressive, she pretends that the rules are her husband's and not hers. Again a bit of a conundrum in her character ... She tries to portray herself as being something she is not ... in that, what is the real Umaben is not clear at all.
As for her dislike towards Chhanchhan, that started with the Purvi incident, and it shows that Umaben carries very deep grudges indeed.
Her first impression of Chhanchhan was unfavourable ... Chhanchhan accused her of bribing the temple priest ... which she DID 😛 ... then of seeking dowry and sugar-coating the demands with more acceptable terms ... which again she DID ... so Chhanchhan both times showed up her true nature, instead of allowing her to get away with her image intact.
That was a lot of analysis ... leaving it open to discussion now!!! 😆