With a few exceptions, electronic transmissions are a legal alternative to paper documents for all transactions - both commercial and consumer. ESIGN applicability can only be determined on a document-by-document basis.
Your question covers a wide range of transactions and related documents. Some of these documents are required by state or federal law and others are not. Unless a document is required by law, is necessary to document your compliance with a law, or is necessary to support a contract with your customer, you are free to handle it any way you wish. Considering that not all customers care to use electronics for some or all of their communications with your company, it's always a good business practice to provide alternate means of document delivery.
Since contract documents fall under state laws and will be judged in a California court, these items must conform to state laws for content, timing, and method of delivery. Although these documents can be handled in electronic form, delivery must conform with either ESIGN or California's UETA.
Disclosures (if any) required by state law are handled the same way.
Federal consumer disclosures can also be handled electronically, but they fall into three delivery categories. Most demanding are "written" communications. If a federal law or regulation says you must deliver something "in writing", then you must use paper or ESIGN-enabled electronic communication. A few federal items must comply with standards specified in a particular law, but need not follow the full ESIGN regimen. Remaining federal items can be handled any way you want. Keep in mind, however, that investor rules will apply to any loan destined for the secondary market.
So how do you sort all of this out? Document by document. A complete ESIGN/UETA analysis matrix would list (column 1) all documents you plan to deliver in electronic form. Column 2 would list the specific (cite the law/reg and section) legal requirement (if any) satisfied by each document. Column 3 would be an indication of the delivery method ("written", regulated, or unrestricted) required by the law or reg shown in Column 2.