A look at Swedish from the POV of how hard it is for an English speaker to learn it. Compared to other languages, Swedish is pretty easy to learn.
Swedish has the disadvantage of having hundreds of irregular verbs. Swedish also has some difficult phonemes, especially vowels, since Swedish has nine vowels, not including diphthongs. Pronunciation of the ö and å (and sometimes ä, which has a different sound than å) can be difficult. Swedish also has pitch accent. Pronunciation is probably the hardest part of Swedish.
Words can take either an -en or an –ett ending, and there don’t seem to be any rules about which one to use. The same word can have a number of different meanings.
Swedish, like German, has gender, but Swedish gender is quite predictable by looking at the word, unlike German, where deciding which of the three genders to use seems like a spin of the Roulette wheel.
Word order is comparatively free in that one can write a single sentence multiple ways while changing the meaning somewhat. So I didn’t know that can be written the following ways:
det visste jag inte
det visste inte jag
jag visste inte det
jag visste det inte
inte visste jag det
The different ways of writing that sentence depend on context. In particular, the meaning varies in terms of topic and focus.
There is a 3-way contrast in deixis:
Swedish also has the same problematic phrasal verbs that English does:
att slå - beat/hit slå av turn off slå fast settle/establish slå igen close/shut slå igenom become known/be a success slå in wrap in, come true slå ner beat down slå på turn on slå runt overturn slå till hit/strike/slap, strike a deal slå upp open (a book), look s.t. up
Swedish orthography is difficult is learning how to write it, since the spelling seems illogical, like in English. The sj sound in particular can be spelled many different ways. However, Swedish spelling is probably easier than English since Swedish lacks a phonemic schwa, and schwa is the source of many of the problems in English. Where allophonic schwa does appear, it seems to be predictable.
One nice thing about Swedish grammar is that it is similar to English grammar in many ways.
Swedish can be compared to a tube in terms of ease of learning. The basics are harder to learn than in English, but instead of getting more difficult as one progresses as in English, the difficulty of Swedish stays more or less the same from basics to the most complicated. But learning to speak Swedish is easy enough compared to other languages.
Swedish gets a 2.5 rating, easy to average difficulty.