Some Suggestion

Firstly, great plugin, works well.

Glad we can put in HTML into the main text box. May i suggest making the main text box a Word Processor fomat (like Word with Teext Sie, colour etc.) would make it muchs easier for novice users.

Also, an easy way to change the colour of the box the text is contained in rather than the flat black colour, and to change the transparancy

Apart from that, i think it works fairly well

https://www.ads-software.com/extend/plugins/coming-soon-maintenance-mode-ready/