From what I gathered, there are many ways to request something of someone. For
example, consider:  
1. 伝えてくれませんか   
2. 伝えてくれれば助かります (This sounds like _if you relay (the message), I will be saved_ , but my colleagues told me it's more like saying thanks, so its real translation is _I will be thankful if you relay the message_ )  
3. 伝えてくれれば感謝します (This sounds exactly like sentence 2, but I have never heard it before for some reason)  
4. 伝えて欲しいなぁ (This sounds like I am forcing someone to do something)  
5. 伝えてください (Translates to _please relay the message_ , but sounds like I am forcing again, such that he doesn't have a choice)  
6. 伝えてくれるといい

So now the question is, under which circumstances should I say each sentence?
I'm looking for a semi casual-ish style (to put it in a fashion sense, almost
like a man wearing a polo shirt and jeans to work instead of a full body
suit), and also one that doesn't give the impression that I am forcing someone
to do something (like in sentence 4 and 5).
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2020-01-18T07:04:46.617
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2023-05-18T18:08:06.013
2020-01-18T07:37:14.590
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question
conjugations
The many ways to request something from someone else
１。伝えてくれませんか。→ Formally works everywhere.

２。伝えてくれれば助かります。→ To say formally but more like "It will be nice if you relay
the message". I think you already explained it nicely.

３。伝えてくれれば感謝します。→ Yes, this is exactly like 2., but more in "asking" attitude.
I would say "It will be very nice if you relay the message". Of course the
direct translation is "I will thank you if you relay the message", but this is
not a good translation.

４。伝えて欲しいな。→ This is more informal and not really asking. (not forcing, of
course) Direct translation is : "I wish he(but actually he is the one who you
are talking to) relay the message". So it just specifies the wish, not really
asking. Of course this is often used when two speakers are close each other,
and can be rude if you are in formal relationship.

５。伝えてください。→ Also formally works, but compare to 1., this is when you have the
rules to control. And yes, as you said, it can sound more forcing, so people
use often 1..

６。伝えてくれるといい。→ This is mostly used when you are superior to other in terms of
先輩（せんぱい）、先生（せんせい）,etc. Directly, it is not asking anything, but of course you
are asking something to the listener. You can use this to your close friends
or coworkers as well, but not to someone who you just met in formal place.
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2020-01-18T13:46:35.910
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2020-01-18T13:46:35.910
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answer