Magz_builder wrote: (clipped)... Is there any way to solve this - preferably using the regular game, without extra mods... (clipped)
Glass or even open skylights in the roof are a good, day-time, design technique.
Ladders and rails can be used as slatted shutters to cover holes yet still allow light through.
Stairs and slabs have a lighting glitch that allows light to pass through them even though they are supposed to be opaque building blocks. I've used this lighting glitch a lot to create hidden lighting. Look for spots where you can hide a torch behind a screwdriver-rotated slab or stair. Slabs will cover one side; stairs will cover two sides. You may have to ajust your structural design in places to create the necessary layers for this techinque.
If your hall's floor is sitting right on the ground, dig the floor 2 blocks deep, place torches on the bottom layer and then place slabs on the side of the next layer up. If you place a support block one block above to floor you can place your first slab on the support blocks' bottom side then remove the support block. From their set your slabs from the side and they should auto-position to the top half of the 1x1x1 block-space. If not, rotate the slabs in to the top position with the screwdriver. You can either do the whole floor this way or create a pattern of lit tiles.
Default torches aren't the brightest available so the if the stairs and slabs block too much light, place a ladder over the inset torch instead.
Another approach is to use the dark areas to downplay the less important parts of the hall and use multiple torches to accentuate the focal piece of the hall
(an eleborate design in the center of the floor, the throne where the monarch sits, on the long dining tables where the feast is served) or to lead your viewer's eye to the parts of the hall that you want noticed first
(colored wool banners and slab sheilds on the support pillars instead of the plain walls in the background) .
You'll have to tinker with the technique; it's one of those things that is better understood by doing than reading about.
I hope this gives you some ideas. Good luck ;)
Note:- Default torches are coded to emit light at level 11.
- The MInetest sun emits light at 14.
- MoreBlocks "super glow glass" and HomeDecor's "glow lights" emit light at 14.