Both are grammatically correct, the meaning is the same, and neither seems particularly awkward or confusing. I'd say it's personal preference.
I don't think that connected to is an appropriate synonym for became acquainted with: It's too informal and has connotations that cast aspersions on "her" character. I want to ask "How did she become connected to these scholars? Did she sleep with them? Did she marry one of them? Was she hired by one them? Did one of their universities hire her?"
The syntax of this sentence is strange, I think. Rather than
"At the conference, she became acquainted with more than 20 scholars, exhibiting excellent networking skills."
it should probably be
"At the conference, she exhibited excellent networking skills by becoming acquainted with more than twenty scholars."
Tacking "exhibiting excellent networking skills" to the end of the sentence is not good style, IMHO. It modifies nothing. Were it the introductory clause followed by "she became acquainted with... at the conference", then it would modify the following clause. Tacked on to the end of the sentence, though, it just seems ungrammatical to me. I know it's a popular construction for academic writers, because all my Taiwanese biomedical authors constantly use it in sentences that run something like this: "IL-6 levels were higher in group A than in group B, suggesting...." and I always change it to "which suggested that...." Okay, maybe it's just a pet peeve, but it seems to me to be a comma splice.
It'd be different in this sentence: "At the conference, she, exhibiting her excellent networking skills, became acquainted with more than twenty scholars". I still don't like it. The sentence is clunky. It reads poorly to my ears.
Best Answer
With words that end in -ist (often they have a -ism form, but not always), many times the -ist word is a person, and the -istic form is an adjective describing either the person or their philosophy, belief, behavior etc.
For example:
Although this is a common pattern, the -ist and -istic forms are both often accepted as either adjectives or the -ist form is accepted as an attributive modifier (noun adjunct/attributive noun). It seems that what makes one form acceptable with regard to certain words is simply established by convention. Look at this Google NGram for results for:
individualist philosophy
individualistic philosophy
collectivist philosophy
collectivistic philosophy
It shows that in this case individualistic is more frequent than individualist, but collectivist is more frequent than collectivistic. Some dictionaries don't even list "collectivistic" as an inflected form. However, even though this site's spell-checker doesn't recognize "collectivistic", it doesn't mean it's not a word. Many dictionaries recognize it. These differences are probably historical accidents.
Given that some dictionaries recognize the -ist form of the word as an adjective and some don't, in many cases it's not exactly clear whether you're looking at an adjective use or attribute noun use. Random House Kernerman Webster's College Dictionary only lists capitalist as a noun. However American Heritage Dictionary lists it also as an adjective, and defines it as:
I hear terms like "misogynist comments", and although I'd tend to use "misogynistic", many people do this, and plenty of dictionaries give their approval of "misogynist" being an adjective.
In other cases there's a more consistent separation between the -ism, -ist and -istic, such as sadism, sadist and sadistic, where you'll rarely hear people say a "sadist person" or "sadist tendencies", as the word "sadistic" is now overwhelmingly established as standard as the adjective.
So long story short, the -ist/-istic difference for noun/adjective is present in many words, but the word ending with -ist is often used as an adjective or as an attributive noun.
humanist or humanistic
As I mentioned above, each word is different as to which suffix is used. Here are the NGram results for "humanist/humanistic views". They're neck and neck, so take your pick.
You COULD argue, if asked what the difference is, that "humanist" describes things more having to do with a humanist person whereas "humanistic" describes things having to do with humanism, but I really don't think this is the case.