Are there any languages that are more analytic than (or as analytic as) English other than Afrikaans in the Indo-European family?
For those unsure of terminology, "analytic" refers to how many morphemes group together to make a word. Some languages will have lots of morphemes together in a word (Australian and North American languages are famous examples of this) and they are called 'polysynthetic.' A language that has few morphemes together in a word is called 'analytic.' Mandarin is often cited as an example of such a language, where there is often only one morpheme per word.
English is relatively analytic, but not the most analytic. While I can't find any stats for languages as a whole, the ever-reliable WALS database has a feature called "[Inflectional synthesis of the verb]"2. The verb is not a terrible place to look - although it does deprive us of the kinds of polysynthesis in German where adjectives and nouns act as morphemes in larger words.
In this we see that English is, across the world's languages, relatively analytic - being one of 24 languages with only 2-3 morphemes per verb. There are only 5 languages with fewer (0-1 morphemes) as opposed to the remainder of the 145 language sample that have anywhere from 3-13 morpheme slots per verb. Looking at the 24 languages that have only 2-3 morphemes, we see that there aren't many in the Euro-area. There's Finnish, but that's not Indo-European, but Uralic.
This leaves Hindi on the map - a member of the Indo-Aryan branch of the Indo-European family. I have not learned much Hindi, but I have learned Nepali, and I would say that these Indo-European languages have, at the most, only a slightly higher number of morphemes per word. This area would be your best candidate for finding another analytic language of the Indo-European family that is similar to English in terms of morphological density of words.
The picture of the synthesis degree is not very clear in many languages. German and the scandinavian languages are quite synthetic if you count in the frequency of composition, and in Scandinavian and somewhat also in English even compound noun-verb complexes.
Greek and Italian can be said to approach polysynthesis if you regard the rigid templatic verbal phrases of these languages as one-word-structures.