It's very rare to see the characters in character in the LA series these days. I am highly doubting that the script writers for this bothered with such a thing, considering the characterizations. Eri pointing a finger gun and shooting at the criminal, however impressive Otsuka Nene's acting may have been, was out of character.
Perhaps it's due to the fact that Ran seemed strikingly out of character due to Kutsuna's tones not fitting Ran? Possibly also due to the fact that Ran was quite out of character since the start of the show, while Shinichi has his moments where he's convincing as a high school detective.
It may be just me, but despite Shinichi and a number of other characters being out of character, the one who I found to get on my nerves the most in the end was Ran. Sato generally comes next, but one can be biased when they have a preference for a certain actor's portrayal of a character as opposed to others.
But indeed it's true that Shinichi, as either Conan or his teenage self, expressing care for a criminal, advocating for justice rather than truth, is unprecedented, unless I remembered wrong, in canon.
That aside, it seems that Heiji's image in the character list has now been released by the official website. They've been hiding it for a while under a blank image. Matsuzaka Tori looked a bit more Heiji in a
non-costumed image, compared to this, sadly. But I suppose it's difficult to expect much from the LA in terms of costuming. They've likely got a low budget.
http://www.ytv.co.jp/conan-drama/cast/bk09.htmlIn terms of costuming and expressions, Kazuha is likely the one that most closely reminds me of the character in canon, aside from Eri. But who knows how things would go in the next episode. A number of images on their blog regarding the Heiji case too.
http://www.ytv.co.jp/conan-drama/blog/