1. Take a promising language, improve it where necessary.
2. Add excellent support for translation to VHDL and Verilog. The generated HDL code has to be readable, editable, and it has to reflect the structure of the original code more or less 1:1. You also need to support "inline VHDL/Verilog" (like inline assembly in software). Otherwise, your language doesn't integrate into the ecosystem of synthesis software, simulators, vendor-dependent Map/P&R, and existing IP cores, which makes it useless in the real world. This is the main reason why all innovative VHDL/Verilog replacements have failed so far. Without this feature, there's just no way your language is going to gain any significant market share.