assuming you're talking about playing as oak
if you're going around to most battles, you're either getting assists or kills. You're either going to get one or the other.. and it doesnt really matter which. If this isn't the case, you're wasting teleports on pointless battles (meaning no kills) and not using them when your teammates actually do kill someone.
I do find that when I play Oak (probably my best char) I do this same thing.. I grind until level 7 or so on my own, then I'm all over. I generally get most flags as well. Dunno if you're doing it.. but every time a creep wave comes, I surge it and proceed on to w/e else needs to be done. lvl 10 this wipes out everything.. so you don't need to spend a lot of time doing it and yet it gets done. This provides me with enough time to go beat on towers or w/e. I only get Nimoths and Scale Armor for armor, yet it provides enough that you can take out any tower pretty easily.
But, as a general rule of thumb, I will stop what I'm doing (unless if the very heat of battle) and go to the nearest creep wave and surge it down. Also, sometimes it's better to tell your teammates to f*** off for a minute while you beat down a tower. I'll ignore my teammates if I'm left alone to take down a tower. After it's down, I'm all theirs again.
Really tho, most favor points doesn't mean a whole lot. Say you assisted taking out 2 of them and died in the process. Your teammate never dies for the rest of the match and continues to get kills. You were busy fending off 2 of them by yourself while he takes out the towers on one entire side. While you hold down the fort lane and defending your gold flag side, he keeps going back and forth capping mana, gold, and xp flags. You continually port around saving him with clutch shields and assisting on kills that he couldn't have got otherwise. The other team has one person sell all his gear to put it into the citadel. They also had a tb constantly destroying both waves of catapult creeps near the citadel. You get 90 points for assists and winning, your teammate gets killstreak, kills, flags, deaths, winner, towers, gold, and the enemy gets reinforcements, dmg, and cit upgrades. Did you suck that game? No.. but you might have only got 5 more favor points than one of the guys on the other team.