Of Schema, Panda and site structure - Your thoughts?

[SupaMonkey]

Hey guys,
So I have an ancient site, with what by todays standards is coded REALLY badly, it was made about 2 decades ago so you can imagine how outdated the code is (using tables instead of layers, etc etc). Of course, through the years its been hit by Google, looking at its visits history (below) you can see it got hit twice really hard. First time was on Google's introduction of Schema.org. (1) I imagine it got hit so because the sites code isnt up to date / standard and such- you agree?
Second it got hit by Panda #20, not too certain why here - but very well - moving on...

This site used to rank on the top 10/20 for very competitive search terms. I am now in the process of redoing the site entirely:
i) Proper code
ii) New copy written by UK pro
iii) Structure of site going to get updated. Previously naming convention was using underscores instead of dashes.

(2) Do you think I will get this site returned to its former glory with the above changes?
(3) What do you think the best way here is? I am not only fixing the dashes/underscores - but better optimising page names too. I was thinking of doing a dump of my sitemap and then using that to implement a new .htaccess and redirect all pages to their new counterparts. This overkill? too much? I imagine the .htaccess file will be huge. (1k pages, 500 indexed by Google)

Thanks in advance...

 

[blackbeans]

It depends on its backlink equity.

Would you consider it an 'authority' site?

If not, you might want to glean some keyword info off your site and use that info to start a fresh new site.

 

[SupaMonkey]

Every 'SEO Pro' I've had look at it is baffled by how a site thats so 'strong' is doing so poorly. I would definitely consider it an 'authority site'.

 

[bartosimpsonio]

You may be sitting on a treasure there. A 20 year old site can probably be worked fairly quickly into a ranking machine.

 

[SupaMonkey]

Not quite 20 years, sitting on 13 years at the moment - still, I get the impression this thing is going to be quite powerful when I'm done fixing its onsite issues.

 

[bartosimpsonio]

Not quite 20 years, sitting on 13 years at the moment - still, I get the impression this thing is going to be quite powerful when I'm done fixing its onsite issues.

Sometimes all you need is slight on-site changes. Old sites have this special mojo.