I will answer one of your several questions.
There is a line of authority in Canadian law that can lead to exclusion-of-liability clauses being unenforceable.
When there are unusual exclusion clauses, inconsistent with the main purpose of the contract, executed in hasty circumstances, where the contract is long and/or small and the signer's attention is not drawn to the exclusion clauses, courts have been wary to enforce them.
Karroll v. Silver Star Mountain Resorts Ltd., 1988 CanLII 3294 (BC SC):
 ... to allow someone to sign a document where one has reason to believe he is mistaken as to its contents, is not far distant from active misrepresentation.
 In the usual commercial situation, there is no need for the party presenting the document to bring exclusions of liability or onerous terms to the attention of the signing party, nor need he advise him to read the document. In such situations, it is safe to assume that the party signing the contract intends to be bound by its terms.
 But situations may arise which suggest that the party does not intend to be bound by a term. In Tilden the hasty, informal way in which the contract was signed, the fact that the clause excluding liability was inconsistent with the overall purpose of the contract, and the absence of any real opportunity to read and understand the document given its length and the amount of small print on its reverse side, led the Court to conclude that the defendant should have known that the plaintiff had no intention of consenting to the onerous exclusion in question. In these special circumstances, there was a duty on Tilden to take reasonable measures to bring the exclusion clause to the attention of Mr. Clendenning.
Tilden Rent-A-Car Co. v. Clendenning, 1978 CanLII 1446 (Ont. C.A.) said:
In modern commercial practice, many standard form printed documents are signed without being read or understood. In many cases the parties seeking to rely on the terms of the contract know or ought to know that the signature of a party to the contract does not represent the true intention of the signer, and that the party signing is unaware of the stringent and onerous provisions which the standard form contains. Under such circumstances, I am of the opinion that the party seeking to rely on such terms should not be able to do so in the absence of first having taken reasonable measures to draw such terms to the attention of the other party, and, in the absence of such reasonable measures, it is not necessary for the party denying knowledge of such terms to prove either fraud, misrepresentation or non est factum.
In the case at bar, Tilden Rent-A-Car took no steps to alert Mr. Clendenning to the onerous provisions in the standard form of contract presented by it. The clerk could not help but have known that Mr. Clendenning had not in fact read the contract before signing it. Indeed the form of the contract itself with the important provisions on the reverse side and in very small type would discourage even the most cautious customer from endeavouring to read and understand it. Mr. Clendenning was in fact unaware of the exempting provisions. Under such circumstances, it was not open to Tilden Rent-A-Car to rely on those clauses, and it was not incumbent on Mr. Clendenning to establish fraud, misrepresentation or non est factum. Having paid the premium, he was not liable for any damage to the vehicle while being driven by him.
As Lord Denning stated in Neuchatel Asphalte Co. Ltd. v. Barnett,  1 W.L.R. 356 at p. 360: "We do not allow printed forms to be made a trap for the unwary."