I think his first 9 months would be classified as a 2/10 signing, and the past 4 months as a 6/10
I include 'value for money' in that rating as well. If we had picked him up for 1/2m then I would rate him higher.
He is certainly showing a lot more hunger and willigness in his all round play. I don't think playing as a lone striker suits him at all however, and looks much better next to Bamford. He did well to get the assist yesterday.
And that value for money is also relevant to our budget as you rightly say. If we were a club that spends £50-£80m on players, at £10m he would be a bargain. But, and I'm not having a go at other fans (definitely not you, as you've posted a thoughtful comment), but our historical signings over the past 30 years have usually been bargain basement, plucked gems and older players looking for a refresh. A £10m signing for us, as we worry about the budget we have, should be a world beater, a 20 goal a season player, so we judge him, not on price, but on what we assume the percentage of his fee used up our budget. I think that is very important in our thinking - did we blow all our budget on him as a gamble? If we did, he wasn't worth it, if the club knew all about him and thought he would improve and get better and become an asset, then he was.
If your friends go out every night and spend £100 each on steak dinners, but you usually go to the local curry house, and you were invited out, saved up a few quid and spent £50 on a steak, you would expect it to be the best steak you've ever tasted, and you'd be very disappointed, if the portions were small. Whereas your friends would think of it as a reasonable meal for what it cost.
For what it's worth, I think he's a decent enough signing, not a world beater, maybe not Premier League, but he does a very good job for us, and I'm sure he will get better, he already looks less keen and more confident.