Good question ..... But it's not clear from your thread title what the thread is about. I hope you don't mind me saying, but you might get more replies if you reword the title.
When I look round, I'm keen to see examples of pupils work - not just on the walls, but in ex books too. I like to see the work and also the marking of that work. I find it very informative.
Yes, to the school being welcoming to visitors (even if it takes up lots of time and is a bit of a pain) and it is good to have a chance to at least meet the Head or a Deputy, even if the tour isn't done by them.
The interaction between the person leading the tour and your own children and with the children in the school is also telling.
Personally I'm not so keen on pupil led tours (more of a Junior or Secondary thing) as the pupils often can't answer all the questions.
I'd also be attracted by schools that have up to date websites, that seem to want to engage with prospective parents, that are open and honest about things like ofsted/SATs/ results and make those things accessible for those who are interested.
Making clear things like the range of clubs, out of school provision and other practical matters also helps a lot too. Even if theses are on the website, having so wing to give parents who are visiting,with that info can be helpful.
The schools I haven't liked, seem secretive and withholding of information. Whilst some go on about SATs etc too much, those who like to say they do to pay much attention to them, sounddishonest to me and as if they are hiding something...because they all have to take these things seriously in reality....and if you're interested in those things, you want to know the school will keep you informed about them.
And if it's a full scale open evening, a cup of tea being available is good. Don't mind paying for it, but I think it's a good thing and makes you feel welcome.
Schools don't have to go crazy trying to promote themselves with massive marketing campaigns, but being welcoming and supplying information are important.