Plan in terms of the sun/shade requirements of the plants. Its all approximate so don't to find exact numbers for each plant. Deep shade plants, typical good houseplants that don't need a bright window, will do well in 100 foot-candles or less. Usually they will burn in bright light. Regular shade plants would be more like 200-500 foot-candles. Many houseplants will be in this category. They will take over 1,000 foot-candles for short periods but will be damaged if they get it for too long. Part sun plants will be around 1,000-1,500 foot-candles. They can take full sun intensity of perhaps 10,000 foot-candles for short periods. Full sun plants prefer a few thousand foot-candles. Most of them will take full sun intensity of 10,000-15,000 foot-candles for several hours without a problem. The problems will come from heating. Just make sure you have air movement over the plants. Remember that the intensity that a plant can experience naturally would not be sustained for 14 hours, so don't necessarily expect to be able to put even a full sun plant in 10,000 foot-candles for 14 hours every day. Full sun is around 10,000 foot-candles, open shade on a sunny day is around 1,000 foot-candles, deep shade may be as low as 100 foot-candles. Indoors, normal home lighting will be 10-50 foot-candles, perhaps as much as 100 foot-candles in work areas such as a kitchen counter or lit sewing table.

I posted some pictures of our kitchen light installation test. Here in California we are stuck with the rules to comply or "no go". We opted to spring for the LED cans mostly because of the height of the ceiling and changing bulbs. See my post below with pics. Here is a link that might be useful: Pictures of kitchen LED cans

For starters I would ask for your money back. His problems ( wife ) cannot translate into yours. I'm a bit confused about the color, your saying they are a "shade to dark" but calling them bright. If they are to dark you cannot lighten them. If they were to light then MAYBE you could do something, but not with any sort of confidense that the new finish will adhere to what he has already applied. There is another thread a few post down that basically has the same problem. To do it correctly , you need to start over . Strip, sand, stain, and finish. I'm happy to look at the pix for you or you can post them here.

I was getting to the bulb type in the last paragraph of my comment, Doug! :) But I ran out of time typing on my phone when my family came to get me at the coffee shop. Yes, find out if your cans are designed for specific bulbs. I had BR30 in my basement, mixed with some A19. I was about to replace all the A19 with BR30, and then an electricial/lighting guy looked at the older cans and told me the brand and that they were supposed top take A19 by design. If there isn't a specific bulb for your cans, then go ahead and try smaller or different bulbs. I used PAR30, short neck, 2700 K, 1000 Lumen, 25 degree LEDs in my outdoor soffits (PAR30 are the correct bulbs that the cans were designed for), and they look great (to me). They still get a little warm because they are 1000 lumen bulbs. So, be careful with specifications on PAR30 bulbs. Long or short neck, color temperature, brightness (lumens), spread (degrees). Try to get LED PAR30 bulbs. If you go with an incandescent, be very careful to get less than maximum wattage that the cans are rated for. PAR30 (or PAR20) can get hot. Below is a link to the bulbs I bought. You can look around the Satco website for others. I recommend getting a good brand like Satco or similar - you can sometimes find them in better HW stores or through specialty lighting stores, or of course online. https://www.satco.com/s9410.html And attached are some photos, in order: Sylvania PAR30 SN 25 deg (L) vs A19. You can see how splotchy the A19 is. Sylvania PAR30 SN 25 deg (L) vs Satco PAR30 SN 2700 K 40 degree Satco PAR30 SN 2700 K 25 degree (L) vs Satco PAR30 SN 2700 K 40 degree (you can see that the Satco 25 degree has higher output than the Sylvania 25 degree).