Angoulême will be Louis XIX (as he was OTL for all of 30 minutes). But it could be interesting to see. If we leave aside the possibility that Marie Thérèse was infertile (it may have been the stress of everything with the revolution) and Angoulême's neurosathenia (which is a vague description of what was wrong with him, since by definition it is characterized by lassitude, fatigue, headache, and irritability, associated chiefly with emotional disturbance), I think it could have been interesting to see.
@Emperor Constantine said once that motherhood would've had a healing effect on Marie Thérèse, and two sons born in 1813 (when it becomes clear Napoléon's star is on the wane), 1815 (at the Restauration) would probably be regarded as good omens.
Angoulême wasn't "liberal" per se, just that he was more like Louis XVIII than his father was. We'd probably still have the trashcan fire that was Charles X's reign - unless Louvel stabs Artois instead of Berri at the opéra. But definitely no July Monarchy (since even
if Marie Thérèse persuades her husband to abdicate as OTL, the duc de Bourgogne (Louis Auguste Antoine), the dauphin (Louis Antoine)'s eldest son wouldn't need a regent, so there would be no reason for them to go to Louis Philippe. Of course, Marie Thérèse begged Charles X
not to appoint Orléans as regent (citing his father's treachery in the Revolution plus Orléans' own less than stellar reputation in those times), and when the council took the offer of the crown to Louis Philippe, his wife (Marie Amélie of Naples) barred them access and said "take it away, we don't want it" (paraphrased). Then Madame Adélaïde (LP's sister) swept in and responded "Gentlemen, you have done my family a great honor and have secured for France a new king" (paraphrasing).