With the latest Zoho Wiki update, you can add tags to each of your Wiki pages. With tags, you can easily group like pages together and it helps during search too - all pages of a particular tag are listed when a tag is clicked upon.
Zoho Wiki's sharing feature was facing this issue of the sharing mail not being delivered sometimes, thanks to mail service provider filters wrongly classifying it as spam. Now the link that is being sent is visible to the Wiki Administrator (the owner of the Wiki who sends the sharing mail). If you are the Wiki's owner & think the mail has not reached the intended recipient(s), you can now copy-paste the link and send it as a separate mail.
Another pretty useful addition is of the URLs in your page text getting auto-linked once you 'Save' the page. Your Wiki page name titles if present in the page text will auto-link to the appropriate page as well and mail IDs become clickable too (opens your mail client when clicked).