What are the risks in replacing *just* names and addresses myself?
There tend to be some fairly specific formal requirements for wills pertaining to who can sign it, who can witness the signatures, etc. See generally
Wills, Estates and Succession Act, SBC 2009, c 13 ("WESA") §§ 36
et seq. For example, in your OP, you mention that you plan to "send out" the documents for signature, but a valid will must be "signed by 2 or more of the witnesses
in the presence of the will-maker". WESA § 37(1)(c) (emphasis added). There is a risk that you may not strictly comply with all of the requirements such that your new will may be invalid. This requirement I have quoted is just one among many tricky requirements and it is quoted for illustration purposes only.
I want to be very clear that I am not attempting to summarise all of the requirements for wills in this post. There are many requirements and I have not listed them here. You cannot rely on this post as a source of information for how to make a valid will.
The Legislature of British Columbia has explicitly confirmed that persons are entitled to conduct their own legal affairs without retaining a lawyer.
Legal Profession Act, SBC 1998, c 9 ("LPA"), § 15(1)(a). However, by doing so, you take on all the responsibility to research the law and understand what you are doing, including learning estate law.
Under normal principles of contract law, parties are generally free to agree to somewhat unfair bargains. Courts generally do not review contracts for reasonableness. Unconscionability is a ground to set aside contract terms in some cases, but it's much more specific than just the agreement being unfair. The theory behind the general rule is that you are free to retain independent counsel for an appraisal of a proposed agreement before entering it. However, agreements with your own lawyer are special because the lawyer is both your advisor and your counter-party in the agreement, and thus there may be a serious imbalance of power in the drafting of the agreement. Thus, in BC, the common law contract rules have been overridden by the Legislature with respect to contracts with a lawyer.
Subject to conditions, a person who has entered into a contract with a lawyer may apply to the Registrar of the Court to have the contract reviewed to determine whether it is "unfair or unreasonable". LPA § 68(2). If the agreement is indeed "unfair or unreasonable", the Registrar has the power to "modify or cancel the agreement". LPA § 68(6). The decision of the Registrar can be appealed to a judge for further review. LPA § 68(8). There are also separate provisions authorising the Registrar to review specifically a "lawyer's bill" to determine whether the charges contained within are authorised by law. LPA §§ 70-75. This statutory framework provides the appropriate remedy if your true complaint is that your lawyer is charging excessive fees or otherwise has placed unreasonable terms into your agreement with the lawyer.