Welcome! It’s all very exciting, isn’t it? 
@Mbhforum has given you very good advice: begin by defining the specific problems that you want to solve. Many times the choice of devices depends on those specifics. Something that would be a perfect set up for one person would not work at all for another household.
(An obvious example is a household with a large dog who would set off the motion sensors that would work perfectly in another household that didn’t have any pets. The motion sensors are still very good devices – – it’s just that that particular model doesn’t solve all problems. So you need to match what the devices can do to what you need to have done.)
The same thing is true for many items in the home. One family might need a washing machine they can handle very large loads. Another might need a washing machine that fits into a specific space. A person in a wheelchair with a service dog might want a combination unit so that the dog could load and unload the machine. Three different households, three different sets of needs, and they will probably end up selecting three different “perfect” washers.
So begin by thinking about what benefits home automation will give you for specific cases.
Other factors
Of course, you will also have additional factors that enter into device selection: if you want them to all work together, or to work with a specific controller. Your budget. How highly you rate Energy efficiency. Aesthetics of the visible devices. Physical ease-of-use. Etc.
You may also find that the use cases vary from one part of the house to another.
And it’s true – – sometimes you see a device advertised which has a feature you hadn’t even considered, and that gets you thinking about how you can use that particular device. 
Which is good too, it’s just that that’s not usually where we start in terms of home automation.
Home automation is most successful when it solves real problems for real people. So we think about the needs before we think about the brands.
Lighting
Regarding lighting, some people like smart switches, some people like smart bulbs, some people use both in different parts of the house. There’s no one right answer.
Here is a good place to start on the lighting question: