The 34-year-old became the first Finn to win the competition, having beaten top seed and European Ryder Cup hero Henrik Stenson 3 and 1 at London Golf Club on Sunday.
The victory saw him climb 15 places up the rankings as world number five Stenson was left to rue a bogey at the fifth and a wayward tee shot at the eighth that found water.
Following his victory, Ilonen was clear that 2014 now ranked as the best of his career, telling the European Tour website: "We were obviously playing for the trophy as hard as we could, and I came out on top.
"If you look at all the World Rankings and Money List and the tournaments ‑ obviously this [year] is on top."
America's Ben Martin was rewarded for his maiden triumph at the Shriners Hospitals for Children Open as he protected his lead on the final day to clinch the win by two strokes from Kevin Streelman.
The 500 FedExCup points ensures he ties with Sang-Moon Bae for the lead, while it also boosts him 30 places up the rankings to 58th.
Scott Hend's play-off win against Angelo Que at the Hong Kong Open sees him jump 85 places to 133rd.
Hend holed out from five feet at the 18th after Que had bogeyed the same hole, with the Australian going on to secure his sixth Asian Tour victory.