You can try with the fontsize package, which is simply a "KOMA-free" version of scrextend, with few new features. With the fontsize option the \baselineskip is automatically set to 1.2<fontsize>. (In the following example: 1.2*30.2=36,24):
\usepackage[fontsize=30.2pt]{fontsize}
If you prefer you can set any value of \baselineskip, for example, through:
\changefontsize[35]{30.2}
The \baselineskip is set by the first optional argument and must be grater than or equal to the font size given in the second argument.
MWE:
You can use the font you prefer but if the font has optical sizes (for example Latin Modern), unusual things can happen: some larger sizes may appear smaller (see the documentation for details). The example below uses the Cochineal typeface:
\documentclass[12pt]{article}
\usepackage{kantlipsum}
\usepackage[margin=1cm]{geometry}
% a smoothly scalabel font is recommended
\usepackage{cochineal}
\usepackage[fontsize=30.2pt]{fontsize}
% FOR BETTER TUNING:
%\changefontsize[35]{30.2}
% #1: baseline skip
% #2: font size
\begin{document}
\kant[3]
\end{document}
