Let me get back to you as soon as possible regarding your proposal.
关于您的提案，我会尽快回复您。
I'll review this proposal and get back to you as soon as I can.
我将审核该提案，并尽快回复您。
We will get back to you after careful consideration.
我们会在慎重考虑之后回复您。

We will review your suggestion.
我们将审核您的提议。
We will review your suggestion. If you have any additional documents that you'd like us to look at, please don't hesitate to send them to us.
我们将审核您的提议。如果您有任何其他文件想提供给我们，请不要犹豫，立即发给我们。