McCulloch is delighted Boyd and Miller have put pen to paper with the League One champions.
The Gers captain played with both in their previous spells at the club, and knows what they will bring to the side.
Some Light Blues fans are unhappy manager Ally McCoist has gone for more exeprienced players to help their Championship bid.
Miller is now 34, while his strike partner Boyd will be 31 next month.
Many supporters wanted to see Rangers bring in younger players who could help the long-term objectives of the club.
But McCulloch, who is himself 36, feels the new signings will help bring on the promising Murray Park kids who have broken into the first team.
He said: "Kenny's a great signing. In terms of his ability, he's a fantastic player for us to have and there's no problem there. I know him well. We've obviously played for Scotland together and he has been at Rangers before. I can't speak highly enough of him.
"His age is no concern for me and it's just a number. I feel fit after a good summer and Kenny looks after himself, too, so there'll be no issue there.
"Kenny's experience will be vital for us and I think he'll be good for the kids as well, for boys such as Fraser Aird and Lewis Macleod.
"It's great to have someone as experienced like him in the dressing room so that the other boys catch watch and learn from him."
Rangers centre-half McCulloch is looking forward to seeing Boyd and Miller renew their partnership up front in the 2014/15 campaign.
He watched them combine to devastating effect in their previous spell at the Gers and help Walter Smith's side win the title in 2009 and 2010.
And he thinks both Boyd, who netted over 20 goals for Kilmarnock last season, and Miller, will be on target in the second tier in the campaign ahead.
Speaking to the official Rangers website, McCulloch said: "Kris had a great partnership with Kenny and they won us the league pretty convincingly a few years ago.
"They were a great foil for each other. Boydy's my mate and the goals he scored for Rangers, along with the ability he has, mean I'm delighted to see him back. He's changed a lot. He has been away for a few years at different clubs after he left here and has experienced different circumstances.
"Things didn't quite work out the way he wanted them to but he's back in Scotland now and he scored a lot of goals at Kilmarnock last season."