"Any good suggestions in planning the week?"
(a) It will be extremely crowded so don't go expecting to do "everything," as it may well turn out there are just some things you will skip. (b) Early morning is good time to try to hit a couple of key (meaning the highly popular) attractions; also note that they sometimes just open all the parks an hour early during Easter (not on an ee schedule just all the parks) and check for that when there -- they usually don't decide on that until the time comes; (c) Late afternoon (after 3 at Epcot, MGM, and after 4 at MK and AK) to about 7 can be a time to hit a number of attractions that may have had huge lines in the morning such as anything other than Test Track at Epcot or RnR and TOT at MGM or second tier attractions such as Pirates and Haunted Mansion at MK which can have hour or longer lines in mid-morning and then short or none at 4. (d) Most crowded time at any park is 10:30 to about 3 so you might try to plan around those times; (e) Make dinner ps's in advance -- in evening at many restaurants at parks, walk-ups are simply told there is nothing, absolutely nothing available the rest of the night; neveretheless for many restaurants (excluding Character meals and viewing restaurants like Rose & Crown and California Grill) you can get ressies while there by calling the day before, key is just to make sure you have a ressie if you intend to eat. (f) Fast Passes for popular rides can run out for day by noon; if you must still hit one of those popular rides without a FP try going during a parade at a park or during the first Fantasmic at MGM when it has two a night (usually during Easter time it does) as lines are sometimes shorter then -- note "shorter" at that time of year for the top rides means anything under 30 minutes. (g) If there are two Fantasmics a night be aware that the first may require you to get in line an hour early to assure getting in while the second never fills and you can walk in at last minute.
"Which parks which days?"
"Which park or special events for Easter Sunday??"
With newly established early entry days what patterns might emerge are not yet known. However, certain patterns generally always happen during Easter time. MK is extremely crowded every day; it is even more than extremely crowd on Easter Sunday (think sardines); Epcot tends to have its lightest day Easter Sunday and other two parks are also lighter than rest of week -- all due to the fact that practically everyone goes to MK for all its believed "special events."
Now the thing to know: there is nothing that goes on at MK on Easter Sunday that you can't see any other day of the week leading up to Easter; believe me, there is nothing different. MK has an "Easter Parade." That is simply the daily parade at 3 with Easter themed floats added -- but that parade shows every day of the week leading up to Easter so go before Easter if you want to see it. You might see an Easter Bunny in the park (the White Rabbit with a basket) but you may see him also on other days. MK's lighter days (and remember this is relative, lighter just means not as bad as a sardine can) are usually Good Friday and then crowds start to thin a little the Thursday and then Friday after Easter. AK, MGM and Epcot are somewhat lighter on Sat (besides on Easter).
If you are looking for any special events on Easter, you go to the resorts not the parks. The resorts have Easter Egg hunts (plastic eggs with treat inside) to which an Easter Bunny shows up and sometimes a Mrs. and then some, like BoardWalk often have some craft events for kids afterwards.
"Where to eat on Easter Sunday...??"
Chef Mickey's, and at least more recentlly, Park Faire and Cape May, have had Easter brunches; whether all three will next year I do not know. For them you need to reserve well in advance and they have been requiring a credit card to hold. Other than that, the restaurants' operations and menus stay the same as any other day although I have seen some use special menus dressed up to make regular faire look like special Easter meals. Thus, I would just eat dinner at wherever you like.
"What to avoid on which days ??"
See discussion above. Avoid MK on Easter Sunday unless you just must go to say you did it.