my feedback is as follows:
In your (husbands) case: you are paid in dollars and are coming back to usa every 5 months... as long as you have rentry permit and you are paying taxes as local US income AND you are filing state/fed taxes as a RESIDENT, you shoud be ok. However, the officer might look for (or ask for during the interview) your assets in USA like property etc. but i think you should be ok.
In your wife's case: it coudl get complicated. but here is the logic. first, as i understood she is not working in usa, now what woudl prompt her to work in India? thinking from a US perspective, they coudl question and that coudl trigger few more aspects. first, she will have to file taxes as RESIDENT and with foreign income and hence get some waiver only on the foreign income part.
what you dont want to do is that she works and you dont declare her salary as foreign income. if they found out, then thats tax evasion and coudl jeopardize your case.