Making a new print profile for larger font size

[moonexpr]

I would like to increase the font size of the A4 paper from 12pt to 16pt because I am producing the PDFs as booklets. However, I am unfamiliar with the arithmetic to make this work for variables like line height, lines per page, font height, etc. Would somebody have any insights to how I should recalculate these parameters to make this new print profile?

If anybody would like to help tinker with these settings, I am essentially using pdfjam to transform the PDF into a booklet. You can install the pdfjam tool using sudo apt install texlive-extra-utils. Thus, generating the booklet takes both afterwrite and pdfjam:

afterwriting --source play.fountain --config "afterwrite.json" --pdf temp.pdf --overwrite \
    && pdfjam --nup 2x1 temp.pdf --landscape --booklet true --outfile booklet.pdf \
    && rm temp.pdf

Below is the print profile I'd like to implement in js/utils/print-profiles.js:

        "a4-large": {
            paper_size: "a4",
            font_size: 16,
            lines_per_page: 57,
            top_margin: 1.0,
            page_width: 8.27,
            page_height: 11.7,
            left_margin: 1.5,
            right_margin: 1,
            font_width: 0.1,
            font_height: 0.1667,
            line_spacing: 1,
            page_number_top_margin: 0.5,
            dual_max_factor: 0.75,
            title_page: {
                top_start: 3.5,
                left_side: ['notes', 'copyright'],
                right_side: ['draft date', 'date', 'contact']
            },
            scene_heading: {
                feed: 1.5,
                max: A4_DEFAULT_MAX
            },
            action: {
                feed: 1.5,
                max: A4_DEFAULT_MAX
            },
            shot: {
                feed: 1.5,
                max: A4_DEFAULT_MAX
            },
            character: {
                feed: 3.5,
                max: 33
            },
            parenthetical: {
                feed: 3,
                max: 26
            },
            dialogue: {
                feed: 2.5,
                max: 36
            },
            transition: {
                feed: 0.0,
                max: A4_DEFAULT_MAX
            },
            centered: {
                feed: 1.5,
                style: 'center',
                max: A4_DEFAULT_MAX
            },
            synopsis: {
                feed: 0.5,
                max: A4_DEFAULT_MAX,
                italic: true,
                color: '#888888',
                padding: 0,
                feed_with_last_section: true
            },
            section: {
                feed: 0.5,
                max: A4_DEFAULT_MAX,
                color: '#555555',
                level_indent: 0.2
            },
            note: {
                color: '#888888',
                italic: true
            }
        },