I don't think any rewards are going to make towering competitive (at least past the first week or something), because I honestly don't think it was competitive for about the last two years it existed… Even in that last month, it felt like more of a bartering contest to ally with other guilds than it did a competition.
The problem that always existed in towering is that it comes with an "everybody wins" endgame… You can't really lose, and if you just continue to do it eventually you're going to win. That's why I continuously suggested that towering be seasonal, and only the top 3–5 guilds at the end of the season be rewarded. That's why the GST and seasonal leaderboards are usually pretty competitive, you can't talk your way into winning. I really hated that part of towering.
It would make people tower a lot more though. I do agree that looking forward to the NGS is becoming depressing, but when/if it does happen then I think it would fix the vast majority of issues of issues like this.