@SiobhanC welcome to the forum. My advice would be to play around and find out what strategies suit you.
Yes in the past 8 months it would appear you would be able to make the quickest gains lower down the market as evidenced by the price gap between the bottom and top end closing as noted by @Pagey74 and @Ericali advice.
When i joined 8 months ago the top priced player in the squad list was less then £1, it is now £1.50. The top priced player on the index ever was £8.50 (post share split prices) at the end of last march, its now £8.12.
Since that top end price drop the pb/mb dividends on offer have risen by 57% overall but top end player cap has not. Judging by that there is currently a psychological apprehension towards the top end by the market in general. Make your own mind up as to whether you think this will continue moving forward or not. Some people will tell you expensive players are not worth it and their reasons why, others will tell you they are currently available at a discounted price and are ripe for a rocket after a long period of stagnation. Make up your own mind, we all have arseholes with an opinion.
Try to understand the difference between cheap, expensive and value. Some players may be expensive and have no value. some players maybe expensive and are value. some players maybe cheap and have no value, some players maybe cheap and are value. Thats not a directive as to what strategy you should or shouldnt take, only make you aware if you are buying a hold built on sand or granite. You can make a lot of money holding crap over a period of time if you time it right and you you can lose money holding value over a period of time if you time it wrong.
Its a game of 3d chess that takes time to learn, but the learning process could be the most enjoyable and profitable you ever undertake. Some areas of the market you might like others you might not like. Beauty of FI is you get to call it as you see it, avoid what you dont like and put your money where your mouth is.
Find what suits you dependant on your temperament, knowledge, time, appetite for risk, patience and budget. That is more important than the who or whatever end of the market you want or should buy into.