If you insist on the lounge, your options in central Paris are limited to places like the Marriott Rive Gauche, although the Sheraton CDG in T2 has a lounge (but their suites, called junior suites, are small and not fancy, although they genuinely do have two separate rooms).

I'd pick the PdG without hesitation if its location works for you. Otherwise the Westin is very close to the Louvre and there's a W next to the opera house.