The former Wakefield, Leeds and Wests Tigers back-row forward sat out the first three months of the season after breaking a bone in his foot during the warm-up to the opening game and never managed to find the form that persuaded Hull to give him a four-year contract and the captaincy.
It was with that in mind that Ellis opted to retire from the international game last September at the age of 32, sacrificing a chance of playing in the World Cup for the sake of his club.
He had watched Peacock enjoy a new lease of life with Leeds after making the same decision a year earlier and says he is already feeling the benefits of the break.
"It's been my first full pre-season since about 2001 and it's been refreshing," Ellis said at the club's pre-season media day.
"It's been tough and hard work but I enjoy that side of being a professional rugby player.
"I drew inspiration from JP doing that and it's allowed me to lay a few foundations that I haven't been able to in the past.
"Normally I come in around Christmas time and before you know it the friendlies are starting and you are in the thick of it.
"There are not many 'firsts' when you get to my age, but it's nice to be able to do that this time around. Hopefully I'll reap the rewards."
Hull beat off competition from virtually every other club in Super League when Ellis opted to end his successful four-year stay in Sydney with the Tigers, and the player knows he has not yet delivered for his new employers.
"I had to weigh up where I was at and, knowing I've not got that many years left, I want to make the most of what I do have," he said.
"I've been lucky enough to have a good career so far and I want to go out on a high not a whimper.
"It would have been great to play in the World Cup but I just thought stretching it out another year would have had a big knock-on effect for this season.
"The club have looked after me and hopefully they will get the best out of me this year."
It was no surprise when Ellis was re-appointed as captain by new head coach Lee Radford, who succeeded Australian Peter Gentle in the wake of Hull's embarrassing 76-18 play-off defeat at Huddersfield in September, but the player never took his role for granted.
"It's his team now and I thought he might have wanted to make some changes," Ellis said.
"Obviously he's big on Hull lads, having been involved in bringing Hull lads through, and I wouldn't have blamed him if he had have gone down that route.
"Thankfully he gave me the opportunity again to lead the team. The captaincy was a big lure to come to Hull and not to be able to do it in the first year as I would have liked was really disappointing."
Ellis, who will lead Hull in Sunday's friendly derby with Hull KR, has been impressed with the impact Radford has made so far and is confident last year's weaknesses have been identified.
"He's been absolutely brilliant," Ellis said. "You always wonder how someone who has not been retired long will take on a top role but he's got a great rapport with the players.
"He wants the best for this team and he's prepared to tell people what he thinks. All the players respect him for that. I'm really looking forward to the season."