While I agree with J.R.'s comment that your sentences are basically fine, I think at least two could be better.
"I'm concerned about what my mother eats."
is not a problem at all.
"I'm concerned about others a lot."
is less than optimal for two reasons. First, my preference is to use very concerned about others rather than concerned about others a lot, which sounds awkward to me. Second, if you mean what you say ("I tend to think that they are doing all right or everything is all right with them all the time"), then your sentence is actually contradictory, and you don't mean what you say. If you were concerned, you'd be worried that they weren't okay, but you're not worried.
"I'm concerned about my test for tomorrow."
I think it'd be more natural to say "I'm worried about tomorrow's test. I'm usually concerned about others' problems but I worry about myself and my problems.
Taste denotes preference—what you like, what sort of dress or book or cuisine you find pleasing.
Indian cooking is more to my taste than Thai.
Symonds had a taste for the exquisite in art and literature.
Her taste is impeccable: she abhors anything showy or vulgar.
Style denotes the manner in which something is expressed:
Milton's style, for all its Latinity, is violent and excessive, intended to bludgeon the reader into submission.
Chanel brought a new style to the runway, one based on youthful ease and athleticism.
Thus, when you say of a dress that “It’s not my taste”, you mean, literally, that it doesn’t suit your preference, you don’t like it; and when you say “It’s not my style” you mean, literally, that it does not present you as you wish to be seen.
But in conversation one is rarely so precise with language. And in this context what you probably mean is a combination of both ideas: “The style of this dress is not to my taste.” So in practice, the two expressions mean pretty much the same thing.
Similarly, when you are congratulating another woman you probably do not mean to restrict your admiration to either her taste in clothes or her appearance. You mean both, and either expression ought to serve. However; the expression “I like your style” usually means something different: unless you are speaking to a fashion designer, it expresses admiration not merely for the manner of dressing but for the manner of behavior—“I like the way you carry yourself, the attitude towards the world which your actions convey.” So you’re probably better off saying “I like your taste”.
Or you could simply say “That’s a really cute dress!”
Best Answer
"Other than that" can be substituted here, but not "otherwise."
"Otherwise" is generally to express consequences to conditional statements (synonymous with "or else"). For example:
It can also be used to mean "differently" or "anything else." For example:
"Other than that" usually means "separately," or "in addition to that" and can't be substituted into the above sentences. It's mostly used between ideas that have no direct connection, or as a final "catch-all" when listing items or actions.