在市场 - 我要买一些橙子
大家好！
Supposing I want to buy oranges for my house. 我现在在市场。I don't know what to say to the vendor in the following situations. Are there differences in meaning between them (if they are correct, of course).

The vendor puts 6 oranges in the basket.

Situation 1) I want some more oranges.
My guesses :
A) 更多橙子
B) 多一些橙子
C) 多一点儿橙子

Situation 2) I want fewer oranges.
My guesses :
A) 更少橙子
B) 少一些橙子
C) 少一点橙子

I have no clue when I should use 一点 or 更 in situations like those.
Thank you!

Question

在市场 - 我要买一些橙子
大家好！
Supposing I want to buy oranges for my house.  我现在在市场。I don't know what to say to the vendor in the following situations. Are there differences in meaning between them (if they are correct, of course).

The vendor puts 6 oranges in the basket.

Situation 1) I want some more oranges.
My guesses : 
A) 更多橙子
B) 多一些橙子
C) 多一点儿橙子

Situation 2) I want fewer oranges.
My guesses :
A) 更少橙子
B) 少一些橙子
C) 少一点橙子

I have no clue when I should use 一点 or 更 in situations like those.
Thank you!

Answer

What comes to my mind is 给多两个(再给多一点）, 给少两个（给少一点，不要那么多）

Answer

一点 adj, seems like： a little , a small piece of  
 更 adv,  ex. 更多，更少，更强 expresses the comparision. it seems 'much' in english. 
And for both examples, i prefer to use expression used in B and C. they are more politesse, it's important for the situation when you speak to sb you never meet before. Option A is also right but it's not very friendly. It likes a order!
A little difference between 一些 and 一点 
一些 + countable nous ， 一点 +  uncountable nous  but there are always exceptions....

Answer

Frankly speaking, 一点 or 更, are not the suitable vocabularies in these occasions.

My suggestions:

Situation 1) I want some more oranges——再来几个！或者，“再添几个！”。

Situation 2) I want fewer oranges——“够了，够了！要不了那么多。”

够了means That's enough. To pronounce it twice in a little bit hurry. Especially when the vendor is putting more oranges into your basket.