Consolidation has a limited impact on your credit score. Basically, it will create one (or more) new tradelines, with the new lender. The number of tradelines will be based on the number of TYPES of loans that you have. For instance, if you have both subsidized and unsubsidized loans, you will have two tradelines. The new accounts will impact your Average Age of Accounts, but given that your current accounts will remain for around 10 years, I don't think this will drop your average substantially unless those are your only older accounts on your report.
Consolidation can lower your monthly payment, but it may also increase the amount of interest you pay by increasing your payment term. The fact that Loan #1 is over the limit has a very limited impact because it is an installment loan, utilization is not nearly as important with these as with revolving accounts.
The main reason to consolidate is convenience. One payment, one lender website/statement to monitor your loans. It can also lower your payment, but like I said, may increase what you pay in the long run.
