The main problem is that this 14th C period lacks much in the way of contemporary historical accounts. It is dubious that the Ottomans in this period attained the professionalism of later centuries.
Accounts of this period show that many armies were made up of 'vassal' contingents, which varied in loyalty. The Serbians at Ankara seem to have been particularly reliable, while some their contemporaries (Turkomens, Albanians etc) were not.
One of the greater problems is classing the Janissaries. While these make in appearance in the later-half of the 14th C, it is not clear how they were organised, how numerous they were, or indeed, how reliant they were on archers.
Major battles fought in this period include Kossovo (against the Sebs), Nicopolis (against the Hungarians-Crusaders) and Ankara (against Timur)
Orkhan contributed nine light vessels (parascarmi) and 1000 archers that fought alonsgide the Genoese in the Bosphorus 1352.
In 1373 Murad sent 5000 Turkish foot archers to assst the Vemnetians in its war with Padua. The Paduan chronicler noted that in flight they dropped their weapons and ran strongly like the devil. Their arms and scimitars, long hats and exceptional archery skills impressed the local Italians.
Small numbers of Latins probably served with the Ottomans e.g. Jacques de Helley- a French knight.
The Turkish contingents that served with the Catalan Company impressed the hisytorian Muntaner with their valour, loyalty and obedience.
Forces in early 14th C Greece consisted of one force of 1000 horse and 500 fot, destroyed by the Sreb Milutin (c 1311). Another 1300 horse and 800 foot under Halil maintained themselves in Thrace and were joined by many volunteers.
Magistros describes them as being particularly ferocious warriors, having both unlimited greed and a willingness to die to protect their possessions or take someone elses. In truth they fuind that it is very dishonourable for them not to die in war, not to have the frenzy of war operated over their bodies; .
One raiding party used their wagons to create a fortified camp.