actually the ideal diode laser source for show laser would be an array of single mode lasers with a large pitch on the substrate say 0.5 to 1 mm. Collimate the fast axis with an FAC collimate the slow axis with a microlens array and transform the resulting collimated line of emitters into a 2d spot with whatever techniqe you like. Wavelength beam combining could give you the beam quality of a single emitter, but even without that you could have a beam equivalent to a 25x knife edge setup on a footprint of ~20x100mm or so. Funny thing is, that these bars exist in theory since the manufacturers produce the diodes on big wafers with thousands of emitters (with most possibly smaller pitch). Just convince Opnext or Mitsubishi not to cut them into single emitters but bars before coating.