It takes lacquer thinner to remove lacquer---mineral spirits will not do so. What kind of wood are you working with? If it is oak or ash, the grain is the cause of the problem, and I don't know of any method to get stain out of the grain in those two woods.

I am not a lover of pannelling except for maybe real wood in library type setting. I think it would be best to remove the pannelling and do drywall all over where it is now. I also think waiting to do much is a good idea in a new home, you need to wait to see how the spaces function for you before doing anything major and that includes painting. BTW painter panels always look like painted panels and IMO not an attractive look . I think the flooring and the ceilings need a big amount of work so just spend some time living there and seeing how it works . I will sya 70s materials were not great so to keep anyo of them to honor the ers would not be at the top of my list. Waht I see in your ideas books is not hwta this space is right now so spend the next 3 months planning what needs doing .

I would paint the doors. Any color. Without seeing the entire room, or see the colors you are working with throughout the home, I won't suggest a color. I would Beef up the trim moulding around the door(s) keep it white as the featured trim in the room. With the highlighting of the trim/wainscotting, I'd paint the walls a hint of color to show off the features. some fabric on the windows for texture? I would leave the bar the natural wood tone you have going. shelving in the alcove, nice... I would personally go with a black or Ebony shelf, but same... I don't know the look you're going for. Keep the woods in the same family, Is the floor carpet, or an area rug? I'd work on the flooring, Bars and carpet don't go.

I too usually am on Team Wood . If this was vintage circa 1900s beadboard (ie heart pine harvested from the old growth forests that once blanketed North America) I would send the wood police out to your house i you so much as threatened to paint it :-) It really is that rare, and that valuable. However this is not that. Its just budget farmed wood complete with a lot of knots and splinters probably. STILL.... it is wood and retaining some wood texture to break up the monotony of what might become too much paint is an idea worth considering. It does need to be distinctly different from your floor though - have you considered a more heavy bodied whitewash, silver gray, or mid or dark charcoal stain with clear non yellowing top coat, one that would be almost semi-opaque. With a wall paint color to coordinate. Might be worth at least experimenting as part of your decision making process. Youd have to sand anyway in order to paint and the benefit of using a heavy bodied or gel stain means you wouldnt have to sand out every last bit of the previous color. Well its a thought!