Yea...Nec really dropped the ball on advertising, they took a 'CDI' type of approach to it. Spamming small ads in Computer mags and other mags that your typical gamer never read. And the ones that did appear in gaming mags were like that, just bad! Also the choice of games to display were never very appealing, such as JJ&Jeff...try convincing a kid back then to choose between a pic of JJ&Jef or a pic of Mario 2 or 3 at the time and its not hard to see how out of touch Nec was. Bonk is the obvious choice of course but he was never advertised as much as he should have been.
TTi ? Yep they did a little better :-) But still, dont forget they made Jonny Turbo! They may have been better than Nec at advertising but in truth thats not saying much, unless you count chuckling at how bad the ads were [Jonny Turbo just tops the cake].
Sega really dominated advertising at that time, and im a firm believer that was the main reason they were able to become competitive. TV ads which were well done + advertising thier good software as opposed to just average software [like i said before, bonk was under advertised for the TG..which wasnt good].