When you use ODS CSV to create a file that Excel can open, you are only creating a CSV file -- so what you are experiencing is the fact that Excel has a preference for its own algorithm for calculating default column widths and deciding whether a cell is character or numeric or how wrapping should occur.
If you used TAGSETS.EXCELXP, instead of ODS CSV then you would get an XML file which DOES have suboptions to allow you to modify or specify column widths, send Microsoft formats to Excel, etc. The "flavor" of XML that's created is Excel 2003 XML. This is a perfectly acceptable format for Excel, as the XML conforms to the Spreadsheet Markup Language specification as set forth by Microsoft.
The XML file is verbose and larger, sometimes than a "native" binary Excel file, that's what I would expect when comparing the sizes of an ASCII text file (CSV or XML) to a BINARY file (.xls).
In your original post you said you were using ODS CSV and in this last post, you implied that you were getting XML, which suggests that sometime between the first post and this post you have switched from ODS CSV to ODS TAGSETS.EXCELXP.
I don't know about setting Excel parameters using DDE, but this paper does describe how to use the extensive sub-option list for TAGSETS.EXCELXP to perform customizations:
http://www.nesug.org/proceedings/nesug08/ap/ap06.pdf
and you might also find some useful information here:
http://support.sas.com/rnd/papers/2010/under_hood_excelxp.zip
http://support.sas.com/rnd/base/ods/templateFAQ/Excelsamples.html
cynthia