My wife and I go up to the point 3 times a year (first Sun. Mon. Tues. & Wed. they are open, a weekend with the grandchildren during the year and the last weekend they are open). My biggest advice would be stay at the Breakers! It is a little more expensive but early season they do have discounted rooms for platinum pass holders (put in the promo code PASS when reserving online). You get to park the car and not fight parking each day. Staying there get's you early entry and allows you to go back to the room and change if you get to wet on the rides or you need a rest. Plus you can pack sandwiches, etc. to save money on food. Word of caution, there are NO Coffee makers in the rooms! We have a small hamilton-beach kureg we always take up with us. The staff at the Breakers is top-notch and I've always found them more than helpful and friendly.
Keep in mind that if you go before Memorial day, schools are in session which is a plus, but not all the shows are going (plus the new Frontier land will not be open until Memorial day this year).
Make sure to ride the train, especially from the back of the park (near steel vengence) to the front. That section has a lot of boneville to enjoy. The other half is mostly a view of the lake.
You can also get Famous Dave's and carry it back to your room (we have done this after the park has closed. Seems they keep the gates open for an hour after the park closes. Perkins in the Breakers is also great for breakfast, dinner or lunch. Tomo's hibachi grill in the Breakers is our favorite place to eat! Fridays in my opinion is overpriced and can be skipped. You can also order Domino's and they will deliver.
Usually I get in an hour early and ride Maverick. I've ridden in 4 times in a row without getting off in the mornings before the crowds get back there. GateKeeper is the fastest line in the park so never be scared of the size of the line there. Also they don't close the line until the park closes so keep that in mind. Millennium Force has a decent line too but know that if it breaks down don't get out of line. Usually it is only down for about 10-15 minutes.
Tues and Wed are definitely less crowded and you should have no problem covering the park in 2 days. If you have a platinum pass flash it everywhere. Most places (Perkins for example) will give you a discount with it. Also if you have a FunPix season pass make sure to go to the FunPix location at the front of the park to make sure your platinum pass is "synced" so it will work. Just ask them to verify they see it in their system.
Finally dress for the weather. A windbreaker is a MUST. Know that the weather forecast for Sandusky is different than it is for the Point. Temps are a little cooler being on the water.
Hope you have a great time!