Feature summary: I would like an {{#or: parser function added to ParserFunctions. ParserPower provides {{#or:}}, where {{#or:{{{1|}}}|default}} replaces {{#if:{{{1|}}}|{{{1}}}|default}}; and you can include more than 2 arguments to the #or, avoiding nesting ifs.

Use case(s)

• If you want to write {{#if:<!--result of uncached expensive computation, e.g. Cargo or DPL query -->|reuse that result then you'll require two expensive computations. The workaround requires using the variables extension, which would be good to avoid; but {{#or: will simply work.
• Also used as a simple syntax sugar for {{#if: (which is itself a syntax sugar for {{#ifeq

Benefits: Adding an {{#or: parser function to ParserFunctions will encourage cleaner and more efficient code. Its use cases are broadly varied, and I feel it's just as useful compared to #if as #if is compared to #ifeq.