LED bulbs can be purchased in various warmths (color; for example cool white vs warm white), lumen (perceived light intensity), and wattage (which can affect the lumen in each "style" of bulb).
Because I have so many lights, many the cheaper ones and some "professional" quality, and several large transformers and a few smaller ones, and keep most on all night I do use quite a bit of electricity with the halogen bulbs. Depending on which lights I have on my wattage can be 1Kw, 2Kw, 3Kw, etc., using all halogen and incandescent for most hours of the night. I've switched over some of the bulbs to LED in areas where I don't need the brightest lighting. I spent weeks looking at LED replacement bulbs and ordered a few to try out. If you search for "replacement LED bulbs for low voltage landscape lighting" your results will be limited so you have to search "outside the box" Replacement LED bulbs come in a pretty wide variety and the choices are increasing pretty fast. BTW.... many of the fixtures come with a bulb or two included and many are halogen. Some come with the wedge base. These don't go up very high in wattage.
The only Solar lights that are (or have turned out to be) useful to me is two metal wedge, solar lights on one side of the spa housing, that stay lit all night, just enough light to not spoil the mood, but enough to see snakes when going to the spa. On three of the other sides I have motion activated battery operated, small lights, that are LED and have good intensity. They go on pretty quickly and go off pretty quickly. I use rechargeable high amp batteries and they last pretty long before needing recharging. When the deck is dark, and soaking in spa, it's fun to see the lights pop on and off as the raccoons circle the spa. Sometimes the dogs are so quiet I only know they are out there with me when a light pops on as they get up to shift position.
Most of the lights I have closest to the pool, where you can see the light while you are in the pool, which is important in that you don't want the glare in your eyes, are for just enough lighting on the deck, and walkway up against the house, enough for us to see the copperheads at night when they are on the concrete. Yet they aren't so bright as to spoil the "mood" when we want the area not so lit up. These are "pathway" lights and use 18 w wedge bulbs. When we want the area more lit we use a remote controlled fluorescent flood light mounted up on second story deck. One of the LED replacement bulbs I ordered to try in those lights is a little brighter than the 18 watt wedge bulbs, and is a warm white that matches the incandescent wedge bulbs very closely in "warmth"; warmth going from cool white to warm white with tones in between.
As indicated in the above post, you get what you pay for, but you can find that the "professional" type fixtures vary greatly in quality and price. Many of the big box store metal lights in the lower price range $20-35 per will lose their coatings after several years. Some of my "copper" lights are flaking off but turning to a nice weathered "verde" color/texture. Many of the bargain pathway lights will fail at the place where the post connects to the base.
If you spend a lot of time researching on Internet you can find some really good deals on the real professional, and the sort-of professional lights.
I have found some great lights on eBay. I have about 12 man-made rock lights, pretty good sized, where the rock is split horizontally, with bulb in base point up, and then the top part of rock sits on little metal pegs anchored in base. They blend in nicely with our natural environment and give a good deal of light for pathways, with light spreading 360 degrees around the light. I tried LEDs in those but the halogen 60 watt works the best. Reflector is mounted above the bulb on the bottom of top piece of rock. They are really expensive lights and I have not found them sold in the US, online or box stores. What looks to be the same light, sold in Europe, is many times what I paid for them on eBay. I purchased some of these without transformers, and a couple of "sets" came with a transformer. Most transformer that come in sets have a rate for just a little over the wattage needed for the lights in that set.
After adding so many lights, over the years, I basically discarded the included transformers that came with any sets becuase I now use large transformers for most of the lighting. Using the larger transformers makes for less concern when adding lights because of wattage limitations on the transformers, but as I add more lights to each transformer, I have to start counting the amount of wattage in use already.
It is hard to find, in big box stores, wiring any heavier than 12 gauge. It's best to go with 10 gauge from the very start and for especially long runs even 8 gauge. 8 and 10 are much more expensive than 12 gauge and up. With low voltage the voltage can drop drastically by the time you get to the end of line so the heavier the wire the better. If your landscape allows for it you can do a loop configuration so that voltage drop is then not an issue.
Hope this helps a bit.
gg=alice