When I was younger in my career (20's) and worked at smaller companies
Smaller companies can tend to be, overall, much more integrated in terms of families than larger environments- obviously, this varies from workplace to workplace. You socialize more openly, get to know people better and as a result- families can become involved.
Since then, I've moved to a new larger city, and the environment is much more "corporate". Everyone is quite busy, and I don't get into many long discussions about my family and children, nor do I hear much from my co-workers about their family and over the last 8 years can only think of one case where someone brought in their spouse and kids and I met them.
Looking at this it pretty much spells out what the "norm" is here- big city, corporate environment, busy, no long discussions- the pattern here is clear: Work is work. Classically it could be said that in these situations, with these variables, it's the polar opposite of your previous employment.
The most important thing to highlight here is this:
Over the last 8 years can only think of one case where someone brought in their spouse and kids and I met them
Clearly, in this workplace, it's far from the norm. Traditionally in these settings, as a form of almost "office etiquette", employees won't bring their families in at all, it seems.
My wife says she feels a bit left out from my work life (missing going in, seeing where I work, seeing my co-workers, etc.)
The real question here is- is it you that misses them coming in, your Wife, or both of you? The black and white of it sounds more like it's something she misses doing.
From the layout of what you've said it seems that both of you need to accept that this is now a more corporate environment, not the closer-knit or "mixing pot" style workplace you used to be in. Business is business, taking time from work to spend with family rather than work is generally frowned upon.
Everyone understands that there may be exceptions to the rule, requiring you to keep your kid(s) for a period due to childcare issues, or on birthdays your partner dropping by for lunch- but tours, meeting people and seeing what goes on? No.
Bearing in mind that there's a lot of different factors at play here- I come from a mixed background of Healthcare and IT in Australia and the UK, both in centralised and rural locations- but in none of these environments was it ever considered acceptable to have your family, nevermind your partner, do more than briefly drop by for a, forgive the phrasing, "justified" reason.
For one, it can be seen as unprofessional from the standpoint that you are at work, which is to be divided from home- this is an office environment, shared with your coworkers and colleagues. Unless it's more of a "modern" workplace which if not encouraging it, doesn't prevent it, which from what you say this evidently is not, it's something of an unwritten rule to keep the two seperate. As said before, there's exceptions, but common sense applies.
Another is that socially speaking, bigger office environments just plain don't have the same level of a more laid-back view on these things. Bigger companies in big offices aren't exactly known for having employees families swan in and out for "brief visits". If you've not seen it happening, it's a clear sign it's not going to be accepted and it's a change that you and the family need to adapt to rather than the other way round.
Factoring the kids in as well, it's safe to say this isn't a good idea.
However- looking at positives here with a dose of optimistic speculation:
There's nothing stopping you from finding out if there's ever any kind of workplace activities, get-togethers, events or otherwise that mean your family could get involved. From team building to "bring your spouse to work day"- the sky is the limit. If you've been in this environment for as long as you have, if there are any colleagues you get along with well enough, perhaps it's an idea to suggest some kind of meal together or similar- either out or at your home.
This way it brings together the two worlds of home and work together, your wife won't feel left out and it could even be the start of a "thing", taking turns at who hosts, where you go, etc. Bringing families into it can hlp them mingle a bit and over time, bring you closer together- who knows!