Thanks for the informative post Nicpedia and others. For those unaware of the energy and indoor air problems introduced by recessed lighting, Ban the Can and Kick the Can might help. Uncontrolled air movement (even with ICAT) is the main issue, contributing to ice dams, wasted energy, moisture transport and possibly backdrafting combustion appliances, sucking in attached garage air or soil gases like radon. Non-AT cans reportedly leak as much as 20 CFM but even 2CFM times X number of can lights can add up to the same amount of air movement as a fan. I think well designed can lighting has a role to play, particularly for artwork and kitchens. David's threads in lighting forum is helpful for novice can designers and this kitchen design article in FHB has graphics but requires subscription. LED and evolving lighting technology requires special dedication for best enlightenment. From what I understand, manually sealing holes in any recessed cans is a fire hazard and why most experts recommend custom enclosures or tenmat hats as outlined at bottom of this recessed can lights article on FHB. It's a laborious PIA, falling outside typical subcontractor scopes adding to can's upfront costs. Be careful thinking that 1st level or conditioned, unvented attics are safe for cans. Homes leak at floor framing bands and the attic, even with spray foam throughout. Blower door tests prove that recessed can lights are major pathways for unwanted air movement. The bulb acts as the "fire" for the micro-chimney effect. As for gaskets included in trim kit, don't expect the electrical sub to include them. Roof details are often contentious and I agree that spray foam at roof deck is on the rise throughout, mainly thanks to stricter building codes. The point is to never install ducts outside the conditioned space (vented attic or vented crawlspace.) Spray foam at roof deck doesn't necessarily mean better. The main thing is that the spray foam industry is falsely advertising and recommending below code levels of insulation. R-value is a different measurement than air-leakage (blower door). Spray foam insulation should not be allowed to use anything "air movement" to prescribe R-value. R38 = ~11" of open cell (R3.5 per inch). Others seem to go with 5.5" - 7" thick, which is R20 to R25, barely half of prescribed code minimum! Along with the pathetic energy performance of thin spray foam are the moisture concerns. From the research I've read, best practice includes a supply and return from the HVAC system in the attic. If not, spray foam could be contributing to high moisture content in the structural sheathing. Tough to argue with Joe Lstiburek who points to a best case vented attic AND having ductwork in conditioned space. Building higher performing vented (unconditioned) attics requires some important considerations. Eliminating storage, raised heel trusses, and sheathing/taping entire upper ceiling before building interior walls is often necessary. Flat roof lines and full vault ceilings do best with insulation at roof deck but on top of structural sheathing. We often use SIPS for this, especially with timber framing. Open web trusses and walkout basements are better at hosting ductwork. Achieving current code minimum or better energy performance can eliminate the need for long duct runs to exterior walls and windows. Well designed systems have centrally located mechanical spaces, cleverly hidden trunk lines, and supply registers at interior walls. Ducted and ductless mini-splits are other possibilities. It's great to involve an energy rater in upfront decisions but be careful with applying simple paybacks to individual components. Few raters have the experience for proper input, often involving many assumptions at the design stage and the software is designed to not overpromise. Best to follow or exceed current international code minimum prescriptions, especially blower door requirements for cost-effective results.

I'd cross post this in the Kitchen forum for some ideas on layout. You have a lot of space to work with. A larger version of your plan with readable measurements or individual sections will help. 450 footcandles at the counter for work surfaces is good to shoot for. Under cabinet lights can help. You have a lot of pendants over that slim island. Those Liteline fixtures are used in RVs and boats where there isn't any space above the ceiling. But they do put out light at up to 600 lumens for 9w. If you want to see them in action visit an RV dealer. A 5th wheel like a Montana or Jayco Pinnacle will also give you a feel for a slim island. For ambient light you can use 6" recessed IC fixtures and regular A19 bulb configuration leds. These are maybe $4ea in dimmable at Costco. They use 15w and produce 1100 lumens in a flood pattern that lights up a large area.

I have a few of the earlier Halo LEDs 675 lumens) and find them plenty bright for smaller areas. They may seem a bit pricey compared to the no-name cheapies, but I haven't had a failure yet in about 4 years of use. As with most recessed lights, you'd probably want a lot of them for a larger room. Cans aren't so great for room lighting, because they're all direct light, no indirect bouncing off the ceiling. I only use them to keep low ceilings from seeming any lower. Also, be aware that the Halo 600 series efficacy is pretty low for an LED, only 54 lumens per watt for the 2700K. These days most good quality compact fluorescents can do 70+ L/W. Some are over 80 L/W.

What's wrong with the downlights you have? They seem appropriate for the locations. Maybe you need to just re lamp them. What type of bulbs are in the can lights? R series bulbs are usually installed by builders or electricians because they are the very cheapest bulbs they can purchase and should not be used in a home like yours. PAR bulbs even in an LED form will provide you with better quality light to highlight the gallery you have on the second floor. BTW you were ill advised on the lighting for your kitchen The barn doors for the pantry should either be painted white or stained to match your chairs The bead chandelier, though charming, is much too small for over that table and for this kitchen. Some type of linear chandelier would have been a better choice IMO I would have recommended you select the same style chairs for the table that you used at the counter The pendants over the island are too large to be hung that close to the edge of your island and hung too high over the island (for some reason in your photo the pendants don't seem to be the same distance from the edge of each side)