In the context of the Quran I would not mind it at all but only in the context of the Quran. If you read the verse allowing polygamy the first word are "If ye fear that ye shall not be able to deal justly with the orphans". Some Muslims (generally men) interpret this verse as permission to marry 4 wives but the scholars I adhere to state that the verse refers to times in history when women (for reasons of war or major sickness) are left with children to bring up and no husband (because he is dead). If my husband married one of these women, for these reasons and not for love or lust, I would have no problem with it, in fact I would support the decision completely and help her to bring the children up.
And then how come I know of many arabs and Indian muslims and muslims of other nations who have more than one wife in the present era ? There is no dearth of eligible men in their society due to war or sickness .
Also does your husband have to marry the woman ? He can easily take care of them without marrying her as well. Also would you like it if your husband has sex with this second wife and other wives as well ? Just curious.