One other pension plan comment...
I'm going to check out the link to economical 401(k) plan administrator provided earlier in thread, but if you want to give a hand to employees to provide them with another "tool" to work toward financial independence, I think the Simple-IRA often works pretty well. Most people don't want to save more than the Simple-IRA limits and the admin costs to the employer are really low. Basically zero.
Note: With a Simple-IRA, the employer match is basically 3% of wages.
A SEP, BTW, might allow you to contribute only to your or only to your wife's SEP-IRA account... you can exclude employees for a variety of reasons including if they haven't worked three of last five years. (You can also easily exclude teenagers and then workers covered under a collective bargaining agreement.)
Final comment related to employees: I think in many labor markets (including Seattle where we are) you have to provide a decent pension plan in order to attract the sort of employees to your team you actually want. I.e., we don't see offering a good benefits package to employees as just a cost to be shouldered, but as a way to attract the right folks.