I've done it in the past as Ottomans and Aragon. I definitly think Ottos are the easiest followed by France. Aragon is a personal favorite though, you are actually deceptively strong, got one if not the best navy around, which helps defeat the Ottomans early.
General strategy:
I ally Austria, Poland and Hungary (if possible, hungary seems to rival you 99% of the time this patch, so just go with another great power, hopefully rivaled to the Ottos or France/England, maybe ally castille if not rivalled). Sometimes Navarra get no allies by Dec 11, which means you can take the mission to vassalize and eat them. (Annex them, don't vasalize). If this happens you can follow up by going after England, with the help of either France, Burgundy and/or Castille it shouldn't be too hard. In that war get the 2 provinces next to navarra, ceuta from Portugal and if possible Pale in Ireland. It is a big plus to get Burgundy into this war, while their first king is alive there is a good chance for the burgundian inheritance, since he is a commander. If it triggers and goes to Castille it's fantastic, since you'll get it all latter for free. If it goes to Austria it's also alright, since you might have a chance to PU latter on.
Next (or first if you didn't manage to get Navarra, or France had already recovered the english provinces) DoW Bizantium, the aggressive expansion is negligable and the stability hit, while it hurts this early is totally worth it. This war should be easy, get one army to Konstantinople and siege the rest with the other. If you are lucky the Ottomans will attack Bizantium at the same time. In that case vassalize them ASAP, while taking Athens for yourself. You'll then be on a defensive war against the Ottomans, and be able to call all your allies, which assuming you got Poland/Austria and someone else, the war should be fairly easy. If you the Ottos don't attack Bizantium, ally all their rivals (keep in mind it's usually possible to ally the Mamelucks if you improve relations). Take all of Bizantium cores, and one province that you can use to release Bulgaria.
After this your AE should be okay in Europe, so drop France as an ally (if you had them) and release Gascony as a vassal, dow and take all of their cores back. You want to do this war before France gets Elan, and call in Austria, and hopefully Burgundy, if the inheritance didn't fire. France is not that strong early, so you need to weaken them as much as possible.
In between wars with France/the ottomans you can attack Irish minors, try to vasalize Scotland, look for opportunities to get land in Italy. After 1490 focus on Italy since the AE will be much lower once they are out of the hre.
Thing to look out for:
The iberian wedding can fire, and gain you a PU over Spain, which you can integrate for free if they have less then 45ish provinces(don't feed them past that, check the actual number on the decision). It fires very frequently if you and spain have rulers of different genders, you can easily abuse this with the dishinherite mechanic. You start with an old ruler, and a old heir. I usually make my heir a general and hope he dies in the first few years, otherwise I disinherit. While having an old ruler and no heir, there is a good chance for events to fire giving you a female heir with a weak claim (usually pretty good stats too). If you get event, or an heir the normal way you'll probably get the inheritance in the first 10 or so years. Your old ruler should die leaving you with either a female ruler from the event, or a regency (which also triggers thewedding)
Try to get burgundy into your wars at the start, and hope for the inheritance for Castille, same goes when they have no heir.
After you form spain, if you and Austria have France as a rival, and you have no heir, an event can fire giving you an heir from their dinasty. Eventually you might be able to force a PU.
Other than that eat the Otto every time the truce is up, and don't forget to take the random provinces needed like london, and the one in Morocco.
If you don't like Spanish Ideas (colonization is not really your objective here) you can culture shift to Neopolitan once you annex them, andtry to form Italy to get that sweet 25% coring cost.
