I'm not sure I understand. Holodeck adventures are just interactive entertainment, something the most primitive home computers have been capable of producing since the 1980s. A computer program juggles multiple parameters to create responses that make it appear that people with personalities are interacting with you - and computers today can effortlessly pass the Turing test of sounding indistinguishable from a human in a given context. Some computer games exploit this, but few to the fullest, yet it's merely a matter of computing power, and that increases so fast that it's probably way past what's required for TNG or VOY holodrama plots the day past tomorrow if it isn't that today.
The further step of moving the action from a computer screen to a holodeck doesn't sound particularly impressive, either. It's just technology. The leap from no movies to movies was a huge one, for the first time superseding human acting with technology; further such steps won't be leaps in psychological terms. One day, somebody will invent a "forcefield" or a "hard light projector" or whatever; Trek only asks us to assume that this day comes a couple of hundred years from now, and even allows for aliens from outer space to introduce it to us if we are too stupid to invent it ourselves.
Once holographic projections can be made, there's no trick to "kissing" or "killing" them, any more than there would be some great objection to a movie character being kissed or killed instead of just standing around. There's no extra cost attached. It's all in the programming, and we have that today already.
But what about taste and smell? Somehow the holodeck reproduces those--and in exactly the right places and at the right moments.
But Timo, the issue here is that some of the holocharacters become true, independent, self-aware sentients, not just facsimiles; which we know they are, because we're in the third-person omniscient position and can see what the characters can't, including the authors' tone, which makes it plain that these are true sentients and not Turing-passing substitutes.