I think it really depends on how you are as a manger. I play as Celtic and won the league in my first season - beat Rangers to it on the last day of the season
I'm only in my 2nd season and have qualified for the Champions League, just played my first match in the group where I drew with Bayer Leverkusen (was a bit miffed though cos was actually winning 3-1) and am playing AC Milan next.
I've hardly bought any players too - in fact I have only actually bought one and got another two or three on free transfers. One of the players I got on free was Juan Pablo Carrizo, the Argentinian goalkeeper. Another I got on free was Nikos Lyberopoulos, a Greek international striker. He's 35 BUT so far in this 2nd season he's been banging them in for me. I also managed to capture Denilson in my first season as well and he's been really good for me. Other players in my current squad that are playing excellent as well are Ledley, Juarez, Kayal, Hinkel, Majstorovic and even Loovens is playing good for me too. A lot of the current players already in the squad I am getting the best out of. Samaras is a hit and miss for me. Played not too bad towards the end of my first season but so far not much this season, so a very hot and cold player for me (pretty much how he's like in real life
).
As for my training, I have put them all on individual training schedules rather than lumping them together in a Midfield schedule, a Defender schedule etc. I prefer this as it gives me more control over a particular players training where if they were in a group schedule and I wanted to change one players training then I couldn't without it affecting the rest of the players on that same schedule. It's tedious to set up originally but is better in the long run I think - especially for the youth players and is working good so far.
Make sure you put the coaches onto their best section only as well. Rather than having them assigned to all sections, for instance, just tick the section that they are best at, whether that be Tactics, Defending, Shooting or whatever. That way you get the best out of your coaches as they are concentrating on what they are best at. For my training, each section for me is Strength - 4.5 stars; Aerobics - 5 stars; Goalkeeping Shot Stopping & Handling - 3 stars (looking to improve this though); Tactics - 4.5 stars; Ball Control - 4.5 stars; Defending - 4 stars; Attacking - 4 stars; Shooting - 4 stars. The more adequate the coach is then the better the training.
My tactics vary from match to match as well - who I'm playing, the quality of opposition, if I'm away or at home etc. I like having 3 in center of midfield with Juarez, Ledly and Kayal and I play two attacking wingmen as well. I have four at the back usually with Mulgrew/Izaguirre and Hinkel in wing back positions, but I have sometimes went with only three at the back giving me a variation of a 3-5-2 sometimes. But like I say, my tactics all depend on who I'm playing and where.