Brian Lara 2005 was genuinely easy it was, like you mentioned for most games, pretty straightforward to play at a RR of 20-25 (even in Tests!)
The problem with these games when batting is that the AI already tells you where the ball with bowl and you can adjust your stance and hit sixes at will. It should only tell you that at the last moment so you had little time to decide which shot to play.
My record's in Brian Lara Cricket 2005 were as follows:
Highest score: Afridi 407
2nd highest score: Salman Butt 399
Highest partnership: 624 (Yk and Moyo - coincidentally this was 6 months before Sanga and Mahega matched my record!

)
My favorite cricket game remains Stick Cricket.
Although playing at a RR of 20-30 is still the norm - the challenge lies in that the AI also scores at the same rate when setting targets!!


The SF and finals of the WorldT20 and T2 World Cup modes are genuinely very challenging - atleast for me
Although you can only hit on the offside and legside (technically can also hit straight but I see no point in doing so as straight balls can still be hoicked to the legside) but you get less than a second to understand the line of the ball during when the fast bowlers are bowling (the hardest for me are the outswing bowlers!)
Spinners and medium pacers can and should be belted for sixes with ease.
It has been around for a while and is very addicting!
The developer however should make sure the teams are being updated frequently - the Pakistan team still has Misbah in the T20 side! lol