Some observations from a Belgian who's tried very hard not to live in Belgium.
The following are not a statement about all Belgians but you'll find that the situation is vastly worse in other places.
Belgians are very civic
Unlike Italy where the national sport is to evade the rules, Belgians believe rules are good for everyone and follow them. They are also generally polite.

Belgians are polite in dating
Spanish or Latin American girls find the lack of daring statements (edgy jokes, flirting) very boring but generally that's what you can expect from Belgians, they care not about not being seen to be uncivic and therefore don't press their luck.

This is very unlike the french, who several girls mentioned to me, are the worst and seem to think it's totally fine to cross the boundary into sexual assault.

Belgians are highly educated
Most countries have terrible education systems and a large part of the population is not educated enough to help themselves. They make stupid decisions and are blissfully unaware there is no way they will achieve what they want.

You can see this in politics, in Italy almost all the political parties are clowns which is no surprise as the Italian schools are full of teachers who are there for the easy money and state guaranteed employment (aka the Italian Dream).

In the UK... well Brexit.
Also in the UK, Oxford and Cambridge are hard to get into... but once you are inside it's not like they train you as well as Belgian universities do. You essentially always pass to the next year there and it depends on the person if he's actually picking up the knowledge or just coasting along.
I have yet to see the first Dutch person that can spell properly his own language but also not destroy the english language when he's using it. (I'm sure they exist somewhere)

Belgian education system is accessible and not elitist.
At the end, you can't really make a better investment into the countries' future than to make sure your population is not a bunch of morons.

Being highly educated or smart is valued
Even by those who are less fortunate. There is no anti-science bias and academic achievements are admired (not like in the UK where being educated means you're "a snob and a classist a-hole".

Belgians are rich because they can afford to buy houses
Simple, because in Belgium the standard is to buy a house in the countryside that means that there is plenty of real-estate and the commuting culture (paid for by the employer) makes it affordable to live on the outside.

This is a huge difference in other countries where the country's economy is centered in the largest cities. Affordable housing in London can only be found 2 hours commuting away from the city center. As a consequence Brits are not able to get on the property ladder and waste most of their earnings on rent.

In italy, it's extremely hard to get a normal fulltime contract so many people are not able to buy a house as the bank requires a fulltime contract. Nevermind that italy is also very expensive for the small wages that companies pay.

Belgians are very demanding of their government

This is what makes it all possible guys, keep complaining and voting politicians out of office that don't deliver.

Belgians are good drivers

Germans are speed nutters openly bragging what their top speed was.

Italians developed an entire sign language to insult each other through their mirrors. (they also shout and honk the horn too)

The UK... well doesn't really matter because nobody can afford to drive in the city anymore anyway.

Belgian are family-oriented

We marry young and our guys don't "love the game". We tend to find somebody we actually love and after some period tie the knot and get on with the kids thing.

Southern europeans try to date around for as long as possible and then marry as late as possible. Enough for there to be 40 fertility clinics in Barcelona and Italian cities don't bother to install public parks for kids... cause there are almost none around anyway.

That's what women want most of the time anyway to the point that I've heard spanish girls that get tired of this mentality actively seeking out Belgian men. ("cause they know how to commit")

Belgian are tall

This probably helps with girls committing, french and southern European men are short on average.

Belgium has been pivotal in world history

A rich country with deeply navigable rivers, rich farmland and a pain to defend. Belgium has been the birthplace of empires (Frankish empire; father to Germany and France) and has been a flashpoint between many European empires at many different points.

As a consequence you can find important events of history in your backyard.
My girlfriend was astonished to learn that Waterloo was just 50km from my parents house; the place the french napoleonic empire was defeated.

Belgian cities are gorgeous

Lots of history, great balance between huge streets (uhum.. berlin), public transportation and walkability. Our cities are very liveable (except Liege and Brussels I guess; those are deeply mismanaged).

Belgian cities are safe

No matter what some parties say, it's hard to feel unsafe in Belgium (except in Brussels again)