The phrase "actually keen" is correct and usable in written English.
It can be used to express genuine enthusiasm or interest in something, often in contrast to a previous assumption or statement.
Example: "I thought she wasn't interested in the project, but she is actually keen to get involved."
Alternatives: "truly eager" or "genuinely enthusiastic".
"I am not actually keen myself on upping the ante," he said.
Instead of making this huge expenditure, if the government is actually keen on serving justice quickly, then more judicial appointments should be made.
David Cameron's head of policy alleged last week that the Lib Dem leader was actually "keen" to raise fees in coalition negotiations despite his party's manifesto commitment.
Mr Obama was actually keen to take a look at the jubilant scene outside, but was prevented from doing do by his extensive security team, according to The Washington Post.
It's like buying insurance, we argue: no fun, but safer than the alternatives.If Mr Davey, a pragmatic sort of chap, cares to shift the British environmental debate onto that sort of argument, I would urge anyone actually keen on saving the earth to cheer.
"They were actually keen when he [Dr Marwan Koukash] took over, he rang the club and said 'we want Morley'," he told BBC Radio Manchester.
Inevitably, there will be a trip there, but I'm actually really keen to take a bit more time this time around, and not do the 'quick fix house kit-out' and try and get some more bits and pieces from antique auctions and so on.
"It would be good for Australia, where the unspoken reality is that Australians are actually quite keen to encourage more immigration from Britain".
"He's entered in the Grand National because, obviously, you have to be from the outset, but none of us are actually very keen to do it this year.
With Papiss Cissé on the way out, possibly to Borussia Dortmund Newcastle are prepared to take Gomis off Lyon's hands and Gomis is actually quite keen on the move.
She wasn't actually too keen on children, but figured she could tolerate them well enough if she could mold hers well enough.
