Most initial takes on a Harishchandra build seem to focused on Butchershop-type decks: NBN kill decks that tag primarily through Midseason Replacements and spend the majority of their influence on Weyland meat damage in the form of Scorched Earth and Traffic Accident. Still, that's hardly the only thing the ID can do as it has numerous strong in-faction synergies, both with tagging effects & cards that manipulate/take advantage of the runner's grip. Some notably strong synergies include:
- Salem's Hospitality
- Targeted Marketing
- Breaking News
- Data Raven
- Other hard-to-avoid tagging ICE like Gutenberg, Turnpike, or even Bandwidth
Out of faction, aside from Weyland meat damage, Snare! is notable for its ability to land a surprise tag. Even if the runner clears tags immediately, the corp gets a peak at their grip. It's worth noting that tag avoidance like New Angeles City Hall & Forger would not trigger the corp's ability.
While a lot of people will stick with the other strong yellow IDs, Harishchandra is primed to be relevant for a long time. Most of the cards listed above are good in their own right & adding even minimal value on top of that makes the identity compelling for tag-based strategies. The 17 influence is almost as gratuitous as it is in Near-Earth Hub.
I think top tiers of competition may not experiment with this ID too much, because at a certain level knowledge of a player's hand adds very little value. Top players know deck archetypes well, are adept at reading board states, & accurately interpret their opponent's moves such that explicitly seeing the opponent's hand isn't hugely beneficial. It doesn't help that, in top cuts or late in tournaments, decklists are mostly known so the Harishchandra ability won't be unveiling surprise splashes like Account Siphon in Shaper or Indexing in Criminal. That's just my guess, could be wrong, it's obviously too early to tell.