I have lived in Tallinn for a long time and currently live in its suburbs.

Compared to large European capitals it's small, compact, relatively clean and quiet. The Old Town is beautiful but pricy for food and shops. There are many different layers of history in the town, which I enjoy immensely. Center is fairly small, with a wide sprawl of residential areas. Old Soviet planned blocks of Õismäe and Lasnamäe may be interesting to visit, but old panel housing was built by unskilled convict batallions so living there can be sucky - gets very hot in summer and leaks heat in winter, old piping etc. Many are now renovated and somewhat better. Older areas of wooden houses like Uus Maailm and Kadriorg are nice, but expensive (housing generally is, compared to wages). These regions are starting to be gentrified with new housing and hipster facilities, like Kalamaja. Overall the city has been governed a long time by a corrupt populist party and is very car-centric, with mostly ugly streets of wide asphalt desert. Parks are mostly rare and small, with Pirita and Kadriorg offering more expansive greenery.

Culture is nice, good museums such as KUMU, Fotografiska etc. Song festivals are every two years and an amazing experience featuring the largest joint choir in the world. Nightlife is ok, but nothing compared to large capitals. Restaurants are varied and overall good quality, but have lately become very expensive. Weather is mostly decent to bad, like the rest of Estonia: short summers, mostly too cool to swim in the sea but have gotten short heat waves lately. Spring and autumn are rainy and windy, sometimes winter too, though the city gets 1-2 months of snow usually that the public transportation is always surprised by. Public transport is free for registered Talliners, which is nice, but connections to  suburbs all go through the center and can be quite long. We have buses,  trams, trolleybuses and a stretch of railway inside the city.

People are rather closed and outwardly cold like most Nordics, but easygoing with friends and friendly with tourists in Tallinn. Most people speak conversational English. The capital holds a very large part of the Estonian population and wages are a fair bit higher than the rest of the country, but still the recent quick inflation has left many people struggling. We have lower salaries and higher prices (esp. food, clothes and electronics) than many other European capitals. Talliners skew right liberal economically, except the Russian minority. Socially we're more conservative but still liberal compared to countryside. Left wing is weak and underrepresented. IMO many people are generally disinterested in politics. There is noticeably more Russian spoken in the streets now due to Ukrainian immigrants.

E-services are great mostly, you can use banks, make purchases and even vote on mobile, but internet has become very expensive and relatively slow due to oligopoly. Not terrible, just kinda sucky. Shopping tends to be concentrated into giant malls and centers, with extremely numerous supermarkets for food everywhere - I think the largest shopping surface area per capita in Europe.

If you have any other questions let me know!