M_SHIRAISHI wrote:

>> 新年あけましたおめでとうございます！
>> 今年もよろしくお願いします。
>
> のほうも、厳密に言えば、少しだけ*オカシイ*です。
>
> 「・・・ございます」と言ったのなら、「お願い*します*」
> ではなくて、「お願い*致します*」と言わなければ、
> 日本語の文章としてのbalance（均衡）が崩れます。
>
> It is as if you  picked a person up and tossed him/
> her into the air, and you suddenly stopped supporting
> him/her,
>
> 後の文を、「今年もよろしくお願いします」 とするので
> あれば、前の文は、「新年あけましたおめでとう！」
> とすべきです。 そうすれば、 balance（均衡）のとれた
> 日本語の文章になります。

Technically, that is correct, and mixing politeness levels is a common
mistake (made even by many young Japanese nowadays) that you should watch
out for. However, I think you will find that it is quite common for friends
and acquaintances to greet each other with 明けましておめでとうございます,
and then continue with 今年も宜しくお願いします。I think the reason is that
you don't really have any medium level of politeness to choose from with 明
けまして. It's either the very informal おめでとう or おめでとうございます.
In fact, if you really want to get technical, wouldn't おめでとう by itself
be wrong anyway? This is the polite form of めでたい which requires a ござい
ます isn't it?

Jeff