How are you printing? Traditional or by scan? If the latter, we won't have to discuss the details, but suffice to say, a film like Portra 400 or 800 can get away with less filtration than normally needed since you can adjust the layers in ways that are hard to adjust in an enlarger.

That being said, for 'proper' filtration, you probably want a filter that goes from 3200K to 5500K, i.e. 80A. Mind you that most interior lights are not at 3200K, but something lower like 2800K, or worse, tungsten/daylight balanced fluorescents with low CRIs. On the other hand, and 80D filter really eats up the light. When I know I'm shooting a lot in tungsten lighting, I use a KB6 filter (like an 80D I think). It's a half correction, from 4400K to 5500K. It brings out the blues a bit and you only lose 1/2 a stop.

For fluorescents, I've never corrected them with a filter. You want some form of minus green, but it's kind of a crap shoot as to what strength you need since the fixtures can be all over the place. Hopefully you are shooting in high CRI lighting. That being said, it's my personal opinion that Portra 400 handles mixed lighting (fluorescents AND tungsten) much better than Portra 800.

For Velvia, or other slide films, you probably want the proper correction, i.e. an 80A. I can't imagine shooting that film in Tungsten lighting through an 80A. That'd be exposure index of 12...

It's a shame Kodak doesn't sell something like Vision3 500T for still cameras. That'd be awesome.