Try this approach. The only problem with Table::Matrix is you have to use tags to color the cells, but it's easy once you get the hang of it. What flexibility problems are you concerned with?

#!/usr/bin/perl
use warnings;
use strict;
use Tk;
use Tk::TableMatrix;

my $mw = MainWindow->new;

my $dataHash = {
"0,0" => "abc",
"0,1" => "123\ndef",
};

my $table = $mw->Scrolled('TableMatrix',
-titlerows => 1,
-roworigin =>  0,
-colorigin  => 0,
-cols => 2,
-rowheight => 2,
-variable => $dataHash,
);

$table->pack(-expand => 1, -fill => 'both');

PushRow(1);

sub PushRow {
my $row = shift;
my $col;
my %ColValue = ( 0 => "ABC", 1 => "456\nDEF" );

for $col (0..1) { $dataHash->{"$row,$col"} = "$ColValue{$col}"; }
}

MainLoop;
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