The Stanley Cup winners don't seem to be recording in the League or Team History screens, nor does the teams finishing position. The Season Leaderboards are also missing (career ones seem fine, though I didn't check the accuracy of the numbers displayed).
Also, some of the younger players have very odd star ratings. Jean Beliveau currently is a 3.5 star player with 0.5 star potential and Dickie Moore is similar. Probably a bug with the player potential ratings not updating when the new season starts and their current ability gets bumped.
There are also issues to work out with the free agency and contract negotiations in historical play. I've got potential free agents telling me they aren't interested in negotiations and want to test the market - they'll be waiting a long time before they get any. If the game is going for historically accurate free agency the players need to be made aware that they have no rights in this era - they'll play for me whether they like it or not
Overall though the historical game seems pretty stable. I've completed three seasons with no crashes and fairly reasonable results. Only issue is the complete lack of player movement - I've initiated a few trades myself but the AI doesn't do any of its own. Might also need a few more short term injuries, but that is just on gut feel.