Murder your darlings

Avoid definitions. Mostly, people can figure out what you mean without doubt from the context. Only use definitions when you are using a word in a specific way that does not align with its ordinary meaning.
- Example: don't define "Tax" if all you mean by tax is any tax, duty, excise, deduction, witholding, impost. [... improvise freely] ... or levy imposed by a competent authority having power to tax.... If your construction will, you know, show up on the Google as a synonym for "tax", then write "tax". If
Use the active tense. Avoid the passive whenever you can.

For the avoidance of doubt: This is an explicit acknowledgment that what you have just written contains doubt. You are a solicitor. You are an officer of the Queen's English. Physician, heal thyself.
"(including, without limitation ...)"
"unless otherwise agreed by the parties": This is true of every english law contract there ever was. The clue is the definition of "contract". It's an agreement between the parties.
"and/or"
"We reserve the right to ..." - Wait a minute: Did you just give that right away? If so, you can't reserve it. If you didn't, you've still got it, so - you know - shut up already.
", whether ... or otherwise," - kill it. Go on, just kill it. You'll feel so much better.
We may, but shall not be obligated to, ...: collapses quite happily down to "we may ...". And while we're on the subject, "obligated" is only a word if you're a prolix American. The English verb is "oblige" and it means "must".
Please be advised/please be aware, please note: If your intended audience is reading and has the intellectual capacity to comprehend your prose, you may be assured it is being advised, becoming aware, and taking note. If it is not, it won't make a damn of difference.
The parties agree that...: A curiously redundant thing to write, it being an agreement and everything. Try something novel - don't say it.