I took some night shots around town the other day at f/2.8 and 1/15th of a second with 100 speed slide film. I am sure that indoors is not a problem with films like Portra 400. You may even have a faster lens than me in which case you can do even better.
Your "indoors" must be way brighter lit than my "indoors." I was shooting some OUTDOOR shots of my wife's family shooting basketball in the driveway in Montgomery, AL on Portra 400, heavy overcast and just before sunset, much brighter than indoors in any night cafe, and getting speeds only about a stop or two better than that - 1/30th and 1/60th at 2.8.
I used to push TMZ to 6400 with pretty good results. So far I haven't tried Delta 3200 at 6400 but I think it will do ok with greatly extended development (at LEAST the Ilford times for 12500.) I've done the "photos of black cats on coal piles at midnight" available light thing far too much since the 70s and kind of want to get a DSLR just for this and family snapshots for which I lack both the time and inclination to work on in the darkroom. Last summer I found myself in New Orleans, in a warehouse at night, watching a clown show by a bunch of tattooed, pierced, clowns doing definitely adult jokes and such, with TMZ loaded into my Pentax LX - even at a potential 6400 I was getting about 1/15th at f/1.7, my fastest lens. I just gave up, put the camera away and enjoyed the show.
If 3200 will suffice you can get really nice black and white results with Delta 3200. (I still have some cold stored barely in date TMZ but that is very soon a complete thing of the past considering how poorly it keeps.) If you need color at that speed or need faster speed in either color or black and white, just go over to the dark side. It's temporary, causes no lasting harm, and really isn't habit forming. It will make you appreciate film when appropriate, and stop the Procrustean attempt to use film at all costs even when it's not the best tool.