[kaels]

I'm no pro at this, but I would do is something more like this:

local function CreateCheckboxes(subframe)
    local boxes = AftermathUIFrame.checkboxes or {}
    
    if subframe == 1 then
        boxes[1] = Checkbox(AftermathhUIFrame, 1, 14, -95, "Show PvP Icon.", AftermathhUI.ouf.showpvpicon)
        boxes[2] = Checkbox(AftermathhUIFrame, 2, 14, -115, "Show Buffs.", AftermathhUI.ouf.showbuffs, ShowBuffs_OnClick)
        boxes[3] = Checkbox(AftermathhUIFrame, 3, 14, -135, "Show Debuffs.", AftermathhUI.ouf.showdebuffs)
        -- and so on
    elseif subframe == 2 then
        boxes[1] = Checkbox(whatever)
    elseif
    else
    end
    for i = i, #boxes do
        boxes[i]:Show()
    end
    AftermathUIFrame.checkboxes = checkboxes
end
 
local function ReleaseCheckboxes()
    local boxes = AftermathUIFrame.checkboxes
    local bin = AftermathUIFrame.recyclebin or {}
    
    for i = 1, #boxes do
        boxes[i]:Hide()
        table.insert(bin, boxes[i])
        boxes[i] = nil
    end
end
 
local function DisplayCheckboxes(subframe)
    ReleaseCheckboxes()
    CreateCheckboxes(subframe)
end
 
AftermathhUIFrameSub1:SetScript("OnClick", DisplayCheckboxes(1))

That lets you keep track of the buttons you've created, recycle them when the user switches tabs so you don't just keep making new buttons, and you can reuse the same code for your other subframes, just adding their button configuration options to the creation function.

You would have to set up your Checkbox function to try to pull old buttons out of the recycle bin before creating new ones and to return the CheckButton object.