Need inspiration for business casual style

[Chocolate Factory]

I'm in my mid 30s and I run my own IT company. I rarely meet clients, so I can basically wear what I want.
I'm a bit torn what to wear - on one hand, I also like a young, sporty, casual look, wearing jeans and sneakers. On the other hand, I'd like to dress better and look a bit more "grown up".
Then again, I travel a whole lot (mostly for leisure) and across climate zones, so I usually wear a large backpack (or I put it on top of my rollaboard trolley when I travel), which I guess doesn't work well with sports jackets. It's extremely practical to just have a light black dune jacket stuffed in my backpack to adjust to different temperatures. I might also want to bike to work in the future (and changing at the office seems like an unnecessary hassle, given that I can wear what I want).
Today I usually wear either chinos or jeans and a polo shirt or a dress shirt (Brooks Brothers) with a merino jumper, and a pair of nice black leather shoes.

Anyway, I really need new pants and I'd also like to invest in a good sports jacket, but I just don't know where to start.
I like this look (except for the t-shirt):

I have also lost a lot of weight (down to 63kg/138lbs on a 1.72m/5'8 frame) and I might gain a bit of weight again in the future as my diet changes.
Where would you get started? Where can I find good pants in Europe? What kind of pants should I get? I guess chinos would be the most versatile option, but I also like thinner, more dress-like pants, as long as they can still look casual.
Where can I find a good sports jacket? What materials should I go for? I'm worried if I just go to a store they might sell me something I won't be satisfied with in the long run. I also feel that most off-the-shelf clothes don't fit me very well.

I travel a whole lot, so I could also have something tailored/adjusted in Thailand or Italy, but again, I'm no expert. The last time I had a suit made in Thailand I ended up almost never wearing it because I didn't like the fit that much.

 

[wozniak]

Style is very personal.

I looked to many sources on youtube for inspiration on business casual and smart casual. Here is one channel I liked for his style. It may not be your choice.

I don't know places in the EU, as what I buy I get from USA or Canada. Many folks like this place in Canada which ships to the USA and elsewhere and has just about everything.